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Visitor

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15 Messages

Monday, April 10th, 2023 10:02 PM

Closed

T3 Timeouts Everyday

​​Hi, I am hoping someone can help me with my issue of having T3 timeouts which happens a few times a day. It is causing my internet to go down for about 1-2 minutes when it happens. I just moved into this house 3 weeks ago and I have been having this problem every since I got here. There was already a line ran to the house from the other owners that lived here before me, so I do not know the history of how this was installed.​​

​​I have already tried calling customer support twice on this issue. The first tech told me I needed to buy a UPS/Batter Backup because there is power flucuation causing the modem to reset. I have never heard of needing one of these for a modem before. I of course did not go and buy one to test this theory. The other tech didn't know anything on how modems worked. He told me, and I quote, "I just sit here and push buttons all day".​​

​​The power coming in from the tap is pretty high so there are 2 attenuators hooked up at the modem, I am pretty sure they are both -6dbm, to get the power in the acceptable ranges. I have done all I can on my end that I can think of to try and fix this issue.​​

​​Today I also got a T4 timeout as well. I have only seen this a few times before. Not sure if this is related to the current issue I am facing or not.​​

​​Below are the stats of my modem. I have a Netgear CM2000.​​

​​Cable Diagnostic​​

​​Status: Good​​

​​Action:​​
​​Your setup looks fine. If you can't access the internet, make sure you properly activated the modem. If modem has been activated and you still can't access the internet, contact your service provider for troubleshooting help.​​
​​If you can access the internet but has other internet issue, the Netgear Cable Knowledge Base can provide additional troubleshooting info.​​

​​CM Status: Good​​

​​Downstream Status: Good​​

​​    Downstream Power Level: Good​​

​​    Downstream SNR Level: Good​​

​​Upstream Status: Good​​

​​    Upstream Power Level: Good​​


​​Current Time: Mon Apr 10 15:23:55 2023​​

​​Startup Procedure​​
​​Acquire Downstream Channel: 417000000 Hz  Locked​​
​​Connectivity State:          OK       Operational​​
​​Boot State:                  OK       Operational​​
​​Security:                   Enabled   BPI+​​
​​IP Provisioning Mode:       Honor MDD   IPv6 only​​


​​Downstream Bonded Channels​​
​​Channel LockedStatus Modulation ChannelID  Frequency     Power    SNR   Correctables Uncorrectables     ​​
​​      1     Locked     QAM256      4     417000000 Hz     1.4     39.3     490357     1485404​​
​​      2     Locked     QAM256      1     399000000 Hz     1.3     39.6     568448     1742801​​
​​      3     Locked     QAM256      2     405000000 Hz     1.4     39.8     393383     1184826​​
​​      4     Locked     QAM256      3     411000000 Hz     1.3     39.8     607123     1879398​​
​​      5     Locked     QAM256      5     423000000 Hz     1.6     40.2     505599     1549441​​
​​      6     Locked     QAM256      6     429000000 Hz     1.7     40.5     704178     2170015​​
​​      7     Locked     QAM256      7     435000000 Hz     2.3     40.4     799888     2497828​​
​​      8     Locked     QAM256      8     441000000 Hz     1.5     40.4     670895     2061712​​
​​      9     Locked     QAM256      9     447000000 Hz     1.3     40.4     919439     2897431​​
​​     10     Locked     QAM256     10     453000000 Hz     1.3     40.2     744755     2278876​​
​​     11     Locked     QAM256     11     459000000 Hz     1.3     40.2     827319     2547817​​
​​     12     Locked     QAM256     12     465000000 Hz     2.1     39.6     789432     2456561​​
​​     13     Locked     QAM256     13     471000000 Hz     2.2     40     739821     2266617​​
​​     14     Locked     QAM256     14     477000000 Hz     1.9     40     966249     3053012​​
​​     15     Locked     QAM256     15     483000000 Hz     1.8     39.9     1161554     3672462​​
​​     16     Locked     QAM256     16     489000000 Hz     1.5     39.5     1291008     4141950​​
​​     17     Locked     QAM256     17     495000000 Hz     1.2     38.9     1017851     3186658​​
​​     18     Locked     QAM256     18     507000000 Hz     1.7     39.1     1086470     3398121​​
​​     19     Locked     QAM256     19     513000000 Hz     1.5     39.4     1230062     3927490​​
​​     20     Locked     QAM256     20     519000000 Hz     1.7     38.6     1215263     3859046​​
​​     21     Locked     QAM256     21     525000000 Hz     1.1     38.9     1335078     4283887​​
​​     22     Locked     QAM256     22     531000000 Hz     0.9     39.4     1523476     4881765​​
​​     23     Locked     QAM256     23     537000000 Hz     0.5     38.5     1417264     4478860​​
​​     24     Locked     QAM256     24     543000000 Hz     1     39.1     1412599     4471985​​
​​     25     Locked     QAM256     25     549000000 Hz     1.4     39.8     1847949     6006364​​
​​     26     Locked     QAM256     26     555000000 Hz     1.5     39.8     1812841     5870645​​
​​     27     Locked     QAM256     27     561000000 Hz     1.3     39.8     1280804     3988808​​
​​     28     Locked     QAM256     28     567000000 Hz     1.3     39.9     1864747     6043975​​
​​     29     Locked     QAM256     29     573000000 Hz     0.8     40.1     1482066     4686403​​
​​     30     Locked     QAM256     30     579000000 Hz     0.6     40     1685022     5397578​​
​​     31     Locked     QAM256     31     585000000 Hz     0.6     40     1964030     6353341​​
​​     32     Locked     QAM256     32     591000000 Hz     0.8     40.1     1738433     5591987​​

​​Upstream Bonded Channels​​
​​Channel   LockedStatus  ChannelType ChannelID   SymbolRate        Frequency       Power     ​​
​​      1       Locked       ATDMA      1       5120 Ksym/sec       35600000 Hz       48.0 dBmV​​
​​      2       Locked       ATDMA      2       5120 Ksym/sec       29200000 Hz       48.5 dBmV​​
​​      3       Locked       ATDMA      3       5120 Ksym/sec       22800000 Hz       48.0 dBmV​​
​​      4       Locked       ATDMA      4       5120 Ksym/sec       16400000 Hz       48.0 dBmV​​
​​      5       Locked       ATDMA      5       2560 Ksym/sec       40400000 Hz       46.0 dBmV​​
​​      6       Locked       ATDMA      6       2560 Ksym/sec       10400000 Hz       47.0 dBmV​​
​​      7       Not Locked       Unknown      0       0       0       0.0​​
​​      8       Not Locked       Unknown      0       0       0       0.0​​

​​Downstream OFDM Channels​​
​​Channel   LockedStatus  ProfileID  ChannelID    Frequency       Power       SNR/MER    ActiveSubcarrier    Unerror    Correctable   Uncorrectable​​
​​      1     Locked     0 ,1 ,2 ,3     193     690000000 Hz     -1.92 dBmV     39.2 dB     1108 ~ 2987     1531051310     1187822673     0​​
​​      2     Not Locked     0      0     0 Hz     0 dBmV     0 dB     0 ~ 4095     0     0     0​​

​​Upstream OFDMA Channels​​
​​Channel   LockedStatus    ProfileID    ChannelID    Frequency       Power​​
​​      1     Not Locked     0      0     0 Hz     0 dBmV​​
​​      2     Not Locked     0      0     0 Hz     0 dBmV​​

​​Event Log​​
​​         Time               Priority     Description​​
​​Mon Apr 10 15:21:26 2023     Critical (3)     Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=;CMTS-MAC=;CM-QOS=1.1;CM-VER=3.1;​​
​​Mon Apr 10 14:21:07 2023     Critical (3)     Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=;CMTS-MAC=;CM-QOS=1.1;CM-VER=3.1;​​
​​Mon Apr 10 12:09:02 2023     Notice (6)     CM-STATUS message sent. Event Type Code: 4; Chan ID: 1 2 3 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=;CMTS-MAC=;CM-QOS=1.1;CM-VER=3.1;​​
​​Mon Apr 10 12:08:56 2023     Warning (5)     MDD message timeout;CM-MAC=;CMTS-MAC=;CM-QOS=1.1;CM-VER=3.1;​​
​​Mon Apr 10 12:08:53 2023     Critical (3)     Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=;CMTS-MAC=;CM-QOS=1.1;CM-VER=3.1;​​
​​Mon Apr 10 11:43:01 2023     Notice (6)     CM-STATUS message sent. Event Type Code: 4; Chan ID: 1 2 3 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=;CMTS-MAC=;CM-QOS=1.1;CM-VER=3.1;​​
​​Mon Apr 10 11:42:52 2023     Warning (5)     MDD message timeout;CM-MAC=;CMTS-MAC=;CM-QOS=1.1;CM-VER=3.1;​​
​​Mon Apr 10 11:42:52 2023     Notice (6)     CM-STATUS message sent. Event Type Code: 5; Chan ID: 10 16 17 24 27; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=;CMTS-MAC=;CM-QOS=1.1;CM-VER=3.1;​​
​​Mon Apr 10 11:42:50 2023     Warning (5)     MDD message timeout;CM-MAC=;CMTS-MAC=;CM-QOS=1.1;CM-VER=3.1;​​
​​Mon Apr 10 11:42:37 2023     Critical (3)     Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=;CMTS-MAC=;CM-QOS=1.1;CM-VER=3.1;​​
​​Mon Apr 10 11:41:57 2023     Notice (6)     CM-STATUS message sent. Event Type Code: 5; Chan ID: 10 16 17 24; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=;CMTS-MAC=;CM-QOS=1.1;CM-VER=3.1;​​
​​Mon Apr 10 11:41:43 2023     Notice (6)     CM-STATUS message sent. Event Type Code: 4; Chan ID: 1 2 3 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=;CMTS-MAC=;CM-QOS=1.1;CM-VER=3.1;​​
​​Mon Apr 10 11:41:27 2023     Notice (6)     CM-STATUS message sent. Event Type Code: 5; Chan ID: 10 16 17 24; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=;CMTS-MAC=;CM-QOS=1.1;CM-VER=3.1;​​
​​Mon Apr 10 11:41:13 2023     Warning (5)     MDD message timeout;CM-MAC=;CMTS-MAC=;CM-QOS=1.1;CM-VER=3.1;​​
​​Mon Apr 10 11:41:02 2023     Critical (3)     Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=;CMTS-MAC=;CM-QOS=1.1;CM-VER=3.1;​​
​​Mon Apr 10 11:34:16 2023     Notice (6)     CM-STATUS message sent. Event Type Code: 4; Chan ID: 12 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=;CMTS-MAC=;CM-QOS=1.1;CM-VER=3.1;​​
​​Mon Apr 10 11:34:01 2023     Warning (5)     MDD message timeout;CM-MAC=;CMTS-MAC=;CM-QOS=1.1;CM-VER=3.1;​​
​​Mon Apr 10 11:25:48 2023     Notice (6)     CM-STATUS message sent. Event Type Code: 4; Chan ID: 12 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=;CMTS-MAC=;CM-QOS=1.1;CM-VER=3.1;​​
​​Mon Apr 10 11:25:47 2023     Warning (5)     MDD message timeout;CM-MAC=;CMTS-MAC=;CM-QOS=1.1;CM-VER=3.1;​​
​​Mon Apr 10 11:22:39 2023     Notice (6)     CM-STATUS message sent. Event Type Code: 5; Chan ID: 10 16 17; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=;CMTS-MAC=;CM-QOS=1.1;CM-VER=3.1;​​
​​Mon Apr 10 11:22:33 2023     Notice (6)     CM-STATUS message sent. Event Type Code: 2; Chan ID: 10; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=;CMTS-MAC=;CM-QOS=1.1;CM-VER=3.1;​​
​​Mon Apr 10 10:01:25 2023     Notice (6)     CM-STATUS message sent. Event Type Code: 4; Chan ID: 12 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=;CMTS-MAC=;CM-QOS=1.1;CM-VER=3.1;​​
​​Mon Apr 10 10:01:00 2023     Warning (5)     MDD message timeout;CM-MAC=;CMTS-MAC=;CM-QOS=1.1;CM-VER=3.1;​​
​​Mon Apr 10 10:00:29 2023     Critical (3)     Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=;CMTS-MAC=;CM-QOS=1.1;CM-VER=3.1;​​
​​Mon Apr 10 09:57:40 2023     Notice (6)     CM-STATUS message sent. Event Type Code: 5; Chan ID: 16 17; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=;CMTS-MAC=;CM-QOS=1.1;CM-VER=3.1;​​
​​Mon Apr 10 09:57:40 2023     Notice (6)     CM-STATUS message sent. Event Type Code: 4; Chan ID: 15 16 17 18 19 21 22 23 27 31 32; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=;CMTS-MAC=;CM-QOS=1.1;CM-VER=3.1;​​
​​Mon Apr 10 09:57:34 2023     Warning (5)     MDD message timeout;CM-MAC=;CMTS-MAC=;CM-QOS=1.1;CM-VER=3.1;​​
​​Mon Apr 10 09:57:17 2023     Notice (6)     CM-STATUS message sent. Event Type Code: 4; Chan ID: 19 21 23 27 31 32; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=;CMTS-MAC=;CM-QOS=1.1;CM-VER=3.1;​​
​​Mon Apr 10 09:57:13 2023     Critical (3)     Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=;CMTS-MAC=;CM-QOS=1.1;CM-VER=3.1;​​
​​Mon Apr 10 09:56:49 2023     Warning (5)     MDD message timeout;CM-MAC=;CMTS-MAC=;CM-QOS=1.1;CM-VER=3.1;​​
​​Mon Apr 10 09:56:18 2023     Critical (3)     Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=;CMTS-MAC=;CM-QOS=1.1;CM-VER=3.1;​​
​​Mon Apr 10 09:45:44 2023     Notice (6)     CM-STATUS message sent. Event Type Code: 4; Chan ID: 21 23 32; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=;CMTS-MAC=;CM-QOS=1.1;CM-VER=3.1;​​
​​Mon Apr 10 09:45:24 2023     Warning (5)     MDD message timeout;CM-MAC=;CMTS-MAC=;CM-QOS=1.1;CM-VER=3.1;​​
​​Mon Apr 10 09:43:02 2023     Critical (3)     Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=;CMTS-MAC=;CM-QOS=1.1;CM-VER=3.1;​​
​​Mon Apr 10 09:39:02 2023     Notice (6)     CM-STATUS message sent. Event Type Code: 4; Chan ID: 32; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=;CMTS-MAC=;CM-QOS=1.1;CM-VER=3.1;​​
​​Mon Apr 10 09:39:00 2023     Warning (5)     MDD message timeout;CM-MAC=;CMTS-MAC=;CM-QOS=1.1;CM-VER=3.1;​​
​​Mon Apr 10 09:37:04 2023     Critical (3)     Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=;CMTS-MAC=;CM-QOS=1.1;CM-VER=3.1;​​
​​Sun Apr 09 15:11:44 2023     Critical (3)     No Ranging Response received - T3 time-out;CM-MAC=;CMTS-MAC=;CM-QOS=1.1;CM-VER=3.1;​​
​​Sun Apr 09 15:11:36 2023     Notice (6)     DS profile assignment change. DS Chan ID: 32; Previous Profile: ; New Profile: 1 2 3.;CM-MAC=;CMTS-MAC=;CM-QOS=1.1;CM-VER=3.1;​​
​​Sun Apr 09 15:11:30 2023     Notice (6)     TLV-11 - unrecognized OID;CM-MAC=;CMTS-MAC=;CM-QOS=1.1;CM-VER=3.1;​​
​​ ​​

Accepted Solution

Visitor

 • 

15 Messages

2 years ago

Problem appears to be fixed now.  Appreantly there was a bunch more damaged lines in the neighborhood that have finally been fixed. Everything seems stable now without issue.

Expert

 • 

110K Messages

@user_edu1411​ 

Thanks for circling back with the update. Hope that things hold up for you !! Best of luck with it !!

I am not a Comcast Employee.
I am a Customer Expert volunteering my time to help other customers here in the Forums.
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Was your question answered? Please mark an Accepted Answer!tick
I am not a Comcast Employee.
I am a Customer Expert volunteering my time to help other customers here in the Forums.
We ask that you post publicly so people with similar questions may benefit from the conversation.

Was your question answered? Please mark an Accepted Answer!tick
I am not a Comcast Employee.
I am a Customer Expert volunteering my time to help other customers here in the Forums.
We ask that you post publicly so people with similar questions may benefit from the conversation.

Was your question answered? Please mark an Accepted Answer!tick
I am not a Comcast Employee.
I am a Customer Expert volunteering my time to help other customers here in the Forums.
We ask that you post publicly so people with similar questions may benefit from the conversation.

Was your question answered? Please mark an Accepted Answer!tick
I am not a Comcast Employee.
I am a Customer Expert volunteering my time to help other customers here in the Forums.
We ask that you post publicly so people with similar questions may benefit from the conversation.

Was your question answered? Please mark an Accepted Answer!tick
I am not a Comcast Employee.
I am a Customer Expert volunteering my time to help other customers here in the Forums.
We ask that you post publicly so people with similar questions may benefit from the conversation.

Was your question answered? Please mark an Accepted Answer!tick

Expert

 • 

110K Messages

2 years ago

Please redact the CM MAC address from the first line of your error log entries for your privacy. They are considered to be personal information. The posting of personally identifiable information is a violation of their forum guidelines. The forum bot will not allow your post to be seen publically. It flagged your post as "Private".

Visitor

 • 

15 Messages

@EG​ Sorry, thought I got them all. It has been removed. I have already got another 400000 uncorrectables since yesterday. I have noticed that I don't always get an error in the event log when I get a surge of uncorrectables. According to the log I have not had another T3 timeout since yesterday evening.

(edited)

Expert

 • 

110K Messages

2 years ago

OK. Are those two attenuators the overall type or are the FPA's (Forward Path Attenuators) ? What are the make and model numbers ?

Visitor

 • 

15 Messages

@EG​ One was already installed when I moved in and it says 12 SVCS  COMMSCOPE. This one seems to affect the downstream and upstream power levels, lowering both about 5-6 dbm. The other is one I bought on Amazon. It is a Holland Electronics FAM-6 attenuator pad, this one only affects the downstream power from the looks of it. The main line in was originally installed into a powered splitter, but since I only need internet, I removed it from the splitter and connected it directly into the modem. I added the -6 attenuator since the downstream power levels were on the high side after removing from the splitter. I was still having the same problem when it was connected into the powered splitter with the 12 SVCS attenuator.

(edited)

Expert

 • 

110K Messages

2 years ago

So this may or may not be the root cause of the problem (YMMV) but the upstream power is on the high side and it may be intermittently fluctuating even higher to out of spec levels. That can cause random disconnects, spontaneous re-booting of the modem, speed, packet loss, latency problems, and the un-bonding of channels.

So you can first try removing the Holland FAM-6 pad and see. It will lower the upstream power down 6 dB to a more desirable range with more wiggle room. And it will raise the downstream power by 6 dB but it will still be OK / in spec. Please post back with what the new power levels are after doing so.

Visitor

 • 

15 Messages

@EG​ I have removed the Holland attenuator. This has brought the power levels for the upstream down a bit. I will give this a shot to see if it does anything. Shouldn't take long to find out.

Cable Diagnostic

Status: Good

Action:
Your setup looks fine. If you can't access the internet, make sure you properly activated the modem. If modem has been activated and you still can't access the internet, contact your service provider for troubleshooting help.
If you can access the internet but has other internet issue, the Netgear Cable Knowledge Base can provide additional troubleshooting info.

CM Status: Good

Downstream Status: Good

    Downstream Power Level: Good

    Downstream SNR Level: Good

Upstream Status: Good

    Upstream Power Level: Good


Current Time: Tue Apr 11 16:52:27 2023

Startup Procedure
Acquire Downstream Channel: 417000000 Hz  Locked
Connectivity State:          OK       Operational
Boot State:                  OK       Operational
Security:                   Enabled   BPI+
IP Provisioning Mode:       Honor MDD   IPv6 only


Downstream Bonded Channels
Channel LockedStatus Modulation ChannelID  Frequency     Power    SNR   Correctables Uncorrectables     
      1     Locked     QAM256      4     417000000 Hz     7.1     41.5     0     0
      2     Locked     QAM256      1     399000000 Hz     6.9     41.3     0     0
      3     Locked     QAM256      2     405000000 Hz     6.9     41.3     0     0
      4     Locked     QAM256      3     411000000 Hz     6.6     41.2     0     0
      5     Locked     QAM256      5     423000000 Hz     7.5     41.7     0     0
      6     Locked     QAM256      6     429000000 Hz     7.3     41.6     0     0
      7     Locked     QAM256      7     435000000 Hz     7.7     41.8     0     0
      8     Locked     QAM256      8     441000000 Hz     7.3     41.7     0     0
      9     Locked     QAM256      9     447000000 Hz     7.5     41.8     0     0
     10     Locked     QAM256     10     453000000 Hz     7.7     41.9     0     0
     11     Locked     QAM256     11     459000000 Hz     7.3     41.7     0     0
     12     Locked     QAM256     12     465000000 Hz     7.5     41.7     0     0
     13     Locked     QAM256     13     471000000 Hz     7.7     41.9     0     0
     14     Locked     QAM256     14     477000000 Hz     7.5     41.8     0     0
     15     Locked     QAM256     15     483000000 Hz     7.5     41.7     0     0
     16     Locked     QAM256     16     489000000 Hz     7.2     41.6     0     0
     17     Locked     QAM256     17     495000000 Hz     7.1     41.5     0     0
     18     Locked     QAM256     18     507000000 Hz     7.3     41.7     0     0
     19     Locked     QAM256     19     513000000 Hz     7.3     41.7     0     0
     20     Locked     QAM256     20     519000000 Hz     7.1     41.6     0     0
     21     Locked     QAM256     21     525000000 Hz     6.7     41.5     0     0
     22     Locked     QAM256     22     531000000 Hz     6.6     41.5     0     0
     23     Locked     QAM256     23     537000000 Hz     6.3     41.3     0     0
     24     Locked     QAM256     24     543000000 Hz     6.5     41.4     0     0
     25     Locked     QAM256     25     549000000 Hz     6.7     41.5     0     0
     26     Locked     QAM256     26     555000000 Hz     6.8     41.6     0     0
     27     Locked     QAM256     27     561000000 Hz     7     41.6     0     0
     28     Locked     QAM256     28     567000000 Hz     6.9     41.5     0     0
     29     Locked     QAM256     29     573000000 Hz     6.6     41.3     0     0
     30     Locked     QAM256     30     579000000 Hz     6.5     41.3     0     0
     31     Locked     QAM256     31     585000000 Hz     6.6     41.3     0     0
     32     Locked     QAM256     32     591000000 Hz     6.6     41.3     0     0

Upstream Bonded Channels
Channel   LockedStatus  ChannelType ChannelID   SymbolRate        Frequency       Power     
      1       Locked       ATDMA      2       5120 Ksym/sec       29200000 Hz       42.5 dBmV
      2       Locked       ATDMA      1       5120 Ksym/sec       35600000 Hz       42.0 dBmV
      3       Locked       ATDMA      3       5120 Ksym/sec       22800000 Hz       42.0 dBmV
      4       Locked       ATDMA      4       5120 Ksym/sec       16400000 Hz       42.0 dBmV
      5       Locked       ATDMA      5       2560 Ksym/sec       40400000 Hz       40.0 dBmV
      6       Locked       ATDMA      6       2560 Ksym/sec       10400000 Hz       41.5 dBmV
      7       Not Locked       Unknown      0       0       0       0.0
      8       Not Locked       Unknown      0       0       0       0.0

Downstream OFDM Channels
Channel   LockedStatus  ProfileID  ChannelID    Frequency       Power       SNR/MER    ActiveSubcarrier    Unerror    Correctable   Uncorrectable
      1     Locked     0 ,1 ,2 ,3     193     690000000 Hz     3.88 dBmV     39.2 dB     1108 ~ 2987     1251019     969272     0
      2     Not Locked     0      0     0 Hz     0 dBmV     0 dB     0 ~ 4095     0     0     0

Upstream OFDMA Channels
Channel   LockedStatus    ProfileID    ChannelID    Frequency       Power
      1     Not Locked     0      0     0 Hz     0 dBmV
      2     Not Locked     0      0     0 Hz     0 dBmV

Visitor

 • 

15 Messages

@EG​ Still getting some uncorrectables, but not nearly as bad. Though it is enough that it is still causing some packet loss. But no T3 timeouts yet. So far it is an improvment. Not sure if there is a good way of getting the downstream power levels lowered a little bit without affecting the upstream power levels will fix that issue or not.

Here are the current stats

Cable Diagnostic

Status: Good

Action:
Your setup looks fine. If you can't access the internet, make sure you properly activated the modem. If modem has been activated and you still can't access the internet, contact your service provider for troubleshooting help.
If you can access the internet but has other internet issue, the Netgear Cable Knowledge Base can provide additional troubleshooting info.

CM Status: Good

Downstream Status: Good

    Downstream Power Level: Good

    Downstream SNR Level: Good

Upstream Status: Good

    Upstream Power Level: Good


Current Time: Wed Apr 12 14:19:09 2023

Startup Procedure
Acquire Downstream Channel: 417000000 Hz  Locked
Connectivity State:          OK       Operational
Boot State:                  OK       Operational
Security:                   Enabled   BPI+
IP Provisioning Mode:       Honor MDD   IPv6 only


Downstream Bonded Channels
Channel LockedStatus Modulation ChannelID  Frequency     Power    SNR   Correctables Uncorrectables     
      1     Locked     QAM256      4     417000000 Hz     6.7     41.3     169     464
      2     Locked     QAM256      1     399000000 Hz     6.4     41.1     173     425
      3     Locked     QAM256      2     405000000 Hz     6.5     41.2     181     450
      4     Locked     QAM256      3     411000000 Hz     6.2     41.1     190     414
      5     Locked     QAM256      5     423000000 Hz     7.1     41.6     201     458
      6     Locked     QAM256      6     429000000 Hz     6.9     41.6     156     542
      7     Locked     QAM256      7     435000000 Hz     7.2     41.7     172     583
      8     Locked     QAM256      8     441000000 Hz     6.7     41.5     274     596
      9     Locked     QAM256      9     447000000 Hz     7     41.6     193     668
     10     Locked     QAM256     10     453000000 Hz     7.3     41.8     223     630
     11     Locked     QAM256     11     459000000 Hz     7     41.6     357     826
     12     Locked     QAM256     12     465000000 Hz     7.2     41.7     363     846
     13     Locked     QAM256     13     471000000 Hz     7.4     41.8     420     831
     14     Locked     QAM256     14     477000000 Hz     7.1     41.7     399     916
     15     Locked     QAM256     15     483000000 Hz     7.2     41.7     529     1072
     16     Locked     QAM256     16     489000000 Hz     6.8     41.5     447     1143
     17     Locked     QAM256     17     495000000 Hz     6.8     41.5     486     1206
     18     Locked     QAM256     18     507000000 Hz     6.9     41.7     516     1465
     19     Locked     QAM256     19     513000000 Hz     7     41.7     630     1437
     20     Locked     QAM256     20     519000000 Hz     6.8     41.6     677     1485
     21     Locked     QAM256     21     525000000 Hz     6.5     41.5     729     1587
     22     Locked     QAM256     22     531000000 Hz     6.4     41.4     749     1630
     23     Locked     QAM256     23     537000000 Hz     6.1     41.3     682     1753
     24     Locked     QAM256     24     543000000 Hz     6.3     41.4     673     1839
     25     Locked     QAM256     25     549000000 Hz     6.5     41.5     811     1839
     26     Locked     QAM256     26     555000000 Hz     6.6     41.5     763     1846
     27     Locked     QAM256     27     561000000 Hz     6.8     41.6     825     1867
     28     Locked     QAM256     28     567000000 Hz     6.7     41.5     743     1978
     29     Locked     QAM256     29     573000000 Hz     6.3     41.3     729     1996
     30     Locked     QAM256     30     579000000 Hz     6.1     41.2     856     1947
     31     Locked     QAM256     31     585000000 Hz     6.1     41.2     773     2029
     32     Locked     QAM256     32     591000000 Hz     6.3     41.2     820     1980

Upstream Bonded Channels
Channel   LockedStatus  ChannelType ChannelID   SymbolRate        Frequency       Power     
      1       Locked       ATDMA      2       5120 Ksym/sec       29200000 Hz       43.0 dBmV
      2       Locked       ATDMA      1       5120 Ksym/sec       35600000 Hz       42.8 dBmV
      3       Locked       ATDMA      3       5120 Ksym/sec       22800000 Hz       42.5 dBmV
      4       Locked       ATDMA      4       5120 Ksym/sec       16400000 Hz       42.5 dBmV
      5       Locked       ATDMA      5       2560 Ksym/sec       40400000 Hz       40.8 dBmV
      6       Locked       ATDMA      6       2560 Ksym/sec       10400000 Hz       41.5 dBmV
      7       Not Locked       Unknown      0       0       0       0.0
      8       Not Locked       Unknown      0       0       0       0.0

Downstream OFDM Channels
Channel   LockedStatus  ProfileID  ChannelID    Frequency       Power       SNR/MER    ActiveSubcarrier    Unerror    Correctable   Uncorrectable
      1     Locked     0 ,1 ,2 ,3     193     690000000 Hz     3.58 dBmV     39.3 dB     1108 ~ 2987     1355629572     939619414     0
      2     Not Locked     0      0     0 Hz     0 dBmV     0 dB     0 ~ 4095     0     0     0

Upstream OFDMA Channels
Channel   LockedStatus    ProfileID    ChannelID    Frequency       Power
      1     Not Locked     0      0     0 Hz     0 dBmV
      2     Not Locked     0      0     0 Hz     0 dBmV

Visitor

 • 

15 Messages

@EG Scratch that, just had 3 T3 timeouts in the last hour.

Expert

 • 

110K Messages

2 years ago

For the Halibut, you can try taking out the 12 SVCS. It's a cable simulator / tilt compensator, not an actual overall attenuator pad. If it doesn't help, you can always put it back inline. I'm curious to see the signal values with it removed so please post them.

Again. Please bear in mind that we may be barking up the wrong tree, so you may need a tech out to investigate this one.

Visitor

 • 

15 Messages

@EG​ Here are the values with it removed.

Cable Diagnostic

Status: Poor

Action:
[Downstream Power Level]
Try these actions (Click the Refresh button after each step):
1) Make sure the coaxial cable is tightly connected.
2) Remove any unnecessary splitters.
3) Replace any required splitters.
4) Contact your service provider for troubleshooting help.

CM Status: Good

Downstream Status: Poor

    Downstream Power Level: Poor
    Downstream power is poor (13.2dBmV). The recommended level is between -10dBmV to 10dBmV.

    Downstream SNR Level: Good

Upstream Status: Good

    Upstream Power Level: Good


Current Time: Wed Apr 12 18:41:54 2023

Startup Procedure
Acquire Downstream Channel: 417000000 Hz  Locked
Connectivity State:          OK       Operational
Boot State:                  OK       Operational
Security:                   Enabled   BPI+
IP Provisioning Mode:       Honor MDD   IPv6 only


Downstream Bonded Channels
Channel LockedStatus Modulation ChannelID  Frequency     Power    SNR   Correctables Uncorrectables     
      1     Locked     QAM256      4     417000000 Hz     11.1     39.3     256     871
      2     Locked     QAM256      1     399000000 Hz     10.5     39.4     142     493
      3     Locked     QAM256      2     405000000 Hz     10.9     39.5     205     527
      4     Locked     QAM256      3     411000000 Hz     10.6     39.5     152     631
      5     Locked     QAM256      5     423000000 Hz     11.2     39.2     217     675
      6     Locked     QAM256      6     429000000 Hz     11.1     39.4     182     685
      7     Locked     QAM256      7     435000000 Hz     11.4     39.3     254     719
      8     Locked     QAM256      8     441000000 Hz     11.4     39.1     347     734
      9     Locked     QAM256      9     447000000 Hz     12.4     39.3     278     905
     10     Locked     QAM256     10     453000000 Hz     12.6     38.9     307     931
     11     Locked     QAM256     11     459000000 Hz     12     39     379     1143
     12     Locked     QAM256     12     465000000 Hz     11.3     39.3     394     1190
     13     Locked     QAM256     13     471000000 Hz     12.4     39.7     402     1199
     14     Locked     QAM256     14     477000000 Hz     12.2     39.9     490     1302
     15     Locked     QAM256     15     483000000 Hz     11.8     39.6     394     1417
     16     Locked     QAM256     16     489000000 Hz     11.9     38.2     511     1420
     17     Locked     QAM256     17     495000000 Hz     12.1     38.7     536     1529
     18     Locked     QAM256     18     507000000 Hz     12.3     38.3     619     1720
     19     Locked     QAM256     19     513000000 Hz     13     38.7     542     1765
     20     Locked     QAM256     20     519000000 Hz     11.8     38.1     687     1838
     21     Locked     QAM256     21     525000000 Hz     11.7     38.1     751     2062
     22     Locked     QAM256     22     531000000 Hz     12.3     37.9     568     2094
     23     Locked     QAM256     23     537000000 Hz     11.7     38.2     794     2146
     24     Locked     QAM256     24     543000000 Hz     12.6     37.9     825     2227
     25     Locked     QAM256     25     549000000 Hz     12.8     37.9     813     2279
     26     Locked     QAM256     26     555000000 Hz     12.6     38     851     2284
     27     Locked     QAM256     27     561000000 Hz     13.1     38.4     938     2562
     28     Locked     QAM256     28     567000000 Hz     13     38.4     837     2431
     29     Locked     QAM256     29     573000000 Hz     12.1     37.3     776     2383
     30     Locked     QAM256     30     579000000 Hz     12.5     37.6     935     2413
     31     Locked     QAM256     31     585000000 Hz     12.4     38.2     850     2380
     32     Locked     QAM256     32     591000000 Hz     13.2     38.5     861     2522

Upstream Bonded Channels
Channel   LockedStatus  ChannelType ChannelID   SymbolRate        Frequency       Power     
      1       Locked       ATDMA      5       2560 Ksym/sec       40400000 Hz       40.0 dBmV
      2       Locked       ATDMA      2       5120 Ksym/sec       29200000 Hz       42.8 dBmV
      3       Locked       ATDMA      3       5120 Ksym/sec       22800000 Hz       42.3 dBmV
      4       Locked       ATDMA      4       5120 Ksym/sec       16400000 Hz       42.0 dBmV
      5       Locked       ATDMA      1       5120 Ksym/sec       35600000 Hz       42.0 dBmV
      6       Locked       ATDMA      6       2560 Ksym/sec       10400000 Hz       41.8 dBmV
      7       Not Locked       Unknown      0       0       0       0.0
      8       Not Locked       Unknown      0       0       0       0.0

Downstream OFDM Channels
Channel   LockedStatus  ProfileID  ChannelID    Frequency       Power       SNR/MER    ActiveSubcarrier    Unerror    Correctable   Uncorrectable
      1     Locked     0 ,1 ,2 ,3     193     690000000 Hz     11.88 dBmV     40.5 dB     1108 ~ 2987     1657537     799827     0
      2     Not Locked     0      0     0 Hz     0 dBmV     0 dB     0 ~ 4095     0     0     0

Upstream OFDMA Channels
Channel   LockedStatus    ProfileID    ChannelID    Frequency       Power
      1     Not Locked     0      0     0 Hz     0 dBmV
      2     Not Locked     0      0     0 Hz     0 dBmV

I got an alert that they will be working in the area early tomorrow morning to try and fix performance issues. I will wait to see if that will make any difference.

Expert

 • 

110K Messages

2 years ago

Put it back in. The downstream power is way too high without it. They may need to adjust / balance the power levels at the line amp on the pole / aerial strand. Please post back again after they are done. Good luck !

Visitor

 • 

15 Messages

@EG​ Alright, will do.

Visitor

 • 

15 Messages

@EG​ Sorry I haven't responded to this in awhile. There apparently was a damaged cable underground from my tap to another tap that they had to replace. Was waiting to see if that was going to fix my issue. It does not look like it has changed much of anything. I am not getting as many T3 Timeouts as I use to, but I am getting a crazy amount of uncorrectables still, anywhere between 1000-200000 at a time. I am trying to get a tech out here, but trying to convince the person on the phone has been challenging. All they keep doing is trying to restart the modem and calling it good. I have tried to tell them that restarting does not fix any issues. I will try again tomorrow to see if I can get the right person on the phone.

Official Employee

 • 

1.4K Messages

Hello @user_edu1411 I see you have been working with @EG, and they are probably the best at deciphering the logs to help figure out where the issue is coming from. Since it seems like it's a signal issue after that outside connection from tap to tap was replaced, I would be happy to book you a repair visit, if you don't have one set already. Please let me know, and we can work from there to make sure things are back to where they should be. 

 

@EG Thank you for all your support, as always! 

 
I am an Official Xfinity Employee.
Official Employees are from multiple teams within Xfinity: CARE, Product, Leadership.
We ask that you post publicly so people with similar questions may benefit from the conversation.
Was your question answered? Please, mark a reply as the Accepted Answer.tick

Visitor

 • 

15 Messages

@XfinityPaula​ I do have a tech coming out tomorrow. I will update on the situation afterwards.

Thanks

Visitor

 • 

15 Messages

@XfinityPaula@EG 

The tech came out yesterday and did not really find anything wrong with the lines, prety much said everything looks perfect in terms of the quality of the cables. He did replace the cable ends on the cable going from the aerial stand to the box on the side of my house and removed the poe moca filter that was attached to the cable on the tap side and replaced it with a new one on a grounding block inside the box on the side of my house, he also replaced the end of the cable on the line going into my house along with a new grounding wire to the grounding rod in the ground. He also removed and took the 12 SVCS cable simulator with him and said that it was old and they do not use them anymore. He just replaced it with a -3.5dbm splitter which just made the power levels too high for comfort so I removed it and put on 2 PPC FPA6-54 in-Line Forward Path Attenuator 6dB, which makes the powerlevels almost perfect on both downstream and upstream. He was not able to do anything about the power coming from the taps since he does not do that and a different tech would need to come out.

Everything is way worse today, I am not sure if it is because it heated up outside a lot more then it has been in the past. I am getting constant correctables and uncorrectables on the modem at pretty much hundreds per second. There is a huge instability of the SNR on the downstream channels. It is constantly moving up and down between about 30-40. I have done absolutley everything I can on my end to fix this. I tried 2 different modems I had and they all did the same thing, so that rules out a modem issue. I tried running a long cable from the box on the side of my house to the modem to make sure there was actually nothing wrong with that cable and that also did not change anything. This was not happening to this extent at all yesterday.

The only thing that is strange about this is it is not affecting my speeds at all, nor really my latency. But if I do a constant ping test I do get a dropped ping once about every 2 minutes or so. This issue seems to be plauging the 32 downstream channels and not really affecting the 1 ofdm channel since that is not having an uncorrectable issue.

Not really sure where to go from here, it appears to be an issue on Xfinitys end. I did call customer support today while this was all happening and they said everything still looks good on their end.

Here are the stats of my modem after about 5 minutes after a reboot. I get an occasional T3 timeout showing up in the log, unless there was a huge spike. But otherwise the log seems pretty quiet which seems strange to me for this issue.

Cable Diagnostic

Status: Good

Action:
Your setup looks fine. If you can't access the internet, make sure you properly activated the modem. If modem has been activated and you still can't access the internet, contact your service provider for troubleshooting help.
If you can access the internet but has other internet issue, the Netgear Cable Knowledge Base can provide additional troubleshooting info.

CM Status: Good

Downstream Status: Good

    Downstream Power Level: Good

    Downstream SNR Level: Good

Upstream Status: Good

    Upstream Power Level: Good


Current Time: Fri May 05 17:35:41 2023

Startup Procedure
Acquire Downstream Channel: 663000000 Hz  Locked
Connectivity State:          OK       Operational
Boot State:                  OK       Operational
Security:                   Enabled   BPI+
IP Provisioning Mode:       Honor MDD   IPv6 only


Downstream Bonded Channels
Channel LockedStatus Modulation ChannelID  Frequency     Power    SNR   Correctables Uncorrectables     
      1     Locked     QAM256     44     663000000 Hz     0.9     38.7     22378     70330
      2     Locked     QAM256     13     471000000 Hz     1.5     39.9     20749     65631
      3     Locked     QAM256     14     477000000 Hz     1.3     39.6     21138     69287
      4     Locked     QAM256     15     483000000 Hz     1.4     39.2     22478     73416
      5     Locked     QAM256     16     489000000 Hz     1.1     39.3     23802     78083
      6     Locked     QAM256     17     495000000 Hz     0.9     39.7     24918     81900
      7     Locked     QAM256     18     507000000 Hz     0.6     40.1     19967     63701
      8     Locked     QAM256     19     513000000 Hz     0.5     39.9     27817     92958
      9     Locked     QAM256     20     519000000 Hz     0.4     40     28879     95447
     10     Locked     QAM256     21     525000000 Hz     -0.1     39.8     30446     99522
     11     Locked     QAM256     22     531000000 Hz     0.3     39.8     14285     44390
     12     Locked     QAM256     23     537000000 Hz     0.2     39     32376     104239
     13     Locked     QAM256     24     543000000 Hz     0.2     38.6     33265     106794
     14     Locked     QAM256     25     549000000 Hz     0     39     32193     108168
     15     Locked     QAM256     26     555000000 Hz     0.8     38.5     22392     71118
     16     Locked     QAM256     27     561000000 Hz     0.7     38.5     33745     111453
     17     Locked     QAM256     28     567000000 Hz     1.1     38.8     33566     112638
     18     Locked     QAM256     29     573000000 Hz     0.6     39.2     21868     67851
     19     Locked     QAM256     30     579000000 Hz     1     39.5     33805     113238
     20     Locked     QAM256     31     585000000 Hz     1.1     38.3     34267     113227
     21     Locked     QAM256     32     591000000 Hz     1.7     39     34464     112978
     22     Locked     QAM256     33     597000000 Hz     1.3     39     33982     114126
     23     Locked     QAM256     34     603000000 Hz     1.4     38.7     34038     112856
     24     Locked     QAM256     35     609000000 Hz     1.3     39.1     34286     112541
     25     Locked     QAM256     36     615000000 Hz     1.1     39     34155     111897
     26     Locked     QAM256     37     621000000 Hz     1     39.3     32980     111310
     27     Locked     QAM256     38     627000000 Hz     1     39.6     33675     109432
     28     Locked     QAM256     39     633000000 Hz     1.3     39.5     33166     109311
     29     Locked     QAM256     40     639000000 Hz     1.3     39.8     32448     106862
     30     Locked     QAM256     41     645000000 Hz     1.1     39.9     32998     105865
     31     Locked     QAM256     42     651000000 Hz     1.1     40.1     32459     105150
     32     Locked     QAM256     43     657000000 Hz     0.7     40.1     31991     104367

Upstream Bonded Channels
Channel   LockedStatus  ChannelType ChannelID   SymbolRate        Frequency       Power     
      1       Locked       ATDMA      1       5120 Ksym/sec       35600000 Hz       45.5 dBmV
      2       Locked       ATDMA      2       5120 Ksym/sec       29200000 Hz       46.0 dBmV
      3       Locked       ATDMA      3       5120 Ksym/sec       22800000 Hz       46.0 dBmV
      4       Locked       ATDMA      4       5120 Ksym/sec       16400000 Hz       45.5 dBmV
      5       Locked       ATDMA      5       2560 Ksym/sec       40400000 Hz       43.8 dBmV
      6       Locked       ATDMA      6       2560 Ksym/sec       10400000 Hz       45.0 dBmV
      7       Not Locked       Unknown      0       0       0       0.0
      8       Not Locked       Unknown      0       0       0       0.0

Downstream OFDM Channels
Channel   LockedStatus  ProfileID  ChannelID    Frequency       Power       SNR/MER    ActiveSubcarrier    Unerror    Correctable   Uncorrectable
      1     Locked     0 ,1 ,2 ,3     193     690000000 Hz     0.58 dBmV     40.4 dB     1108 ~ 2987     4860746     1754783     0
      2     Not Locked     0      0     0 Hz     0 dBmV     0 dB     0 ~ 4095     0     0     0

Upstream OFDMA Channels
Channel   LockedStatus    ProfileID    ChannelID    Frequency       Power
      1     Not Locked     0      0     0 Hz     0 dBmV
      2     Not Locked     0      0     0 Hz     0 dBmV

(edited)

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