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Tech Left and could not figure out the internet issue..

Frequent Visitor

Tech Left and could not figure out the internet issue..

I have been seeing a lot lower speeds then i should be getting. Called a comcast, they sent a tech out but they could not figure the issue  out and said i should call xfinity back....

Troubleshooting moved the modem to 3 different lines, tried 2 modems (xfinity approved). The spliter was even replaced... i was getting around the speeds that i should be getting up until 2 weeks ago.. i should be getting the 1gb download and i am only getting 200-300down.. some days worse..

I even moved the modem to the line closed to the box out side. which goes stright though the wall  and outside to the box.

Can any one help me ? i was getting 900 plus fine up until last week

<tabindex=-1>Startup Procedure</tabindex=-1>
Procedure Status Comment
Acquire Downstream Channel 633000000 Hz Locked
Connectivity State OK Operational
Boot State OK Operational
Configuration File OK d11_m_cm1000_gigabit_c01.cm
Security Enable BPI+
IP Provisioning Mode Honor MDD IPv6 only

<tabindex=-1>Downstream Bonded Channels</tabindex=-1>
Channel Lock Status Modulation Channel ID Frequency Power SNR / MER Unerrored Codewords Correctable Codewords Uncorrectable Codewords
1 Locked QAM256 28 633000000 Hz -6.4 dBmV 40.0 dB 7121092 0 0
2 Locked QAM256 1 471000000 Hz -4.5 dBmV 41.0 dB 5765565 0 0
3 Locked QAM256 2 477000000 Hz -4.5 dBmV 40.6 dB 5769640 0 0
4 Locked QAM256 3 483000000 Hz -4.6 dBmV 40.6 dB 5773441 0 0
5 Locked QAM256 4 489000000 Hz -4.5 dBmV 41.0 dB 5777036 0 0
6 Locked QAM256 5 495000000 Hz -4.4 dBmV 41.0 dB 5780272 0 0
7 Locked QAM256 6 501000000 Hz -4.5 dBmV 41.1 dB 5784656 0 0
8 Locked QAM256 7 507000000 Hz -4.7 dBmV 40.9 dB 5788056 0 0
9 Locked QAM256 8 513000000 Hz -4.5 dBmV 40.9 dB 5792581 0 0
10 Locked QAM256 9 519000000 Hz -4.5 dBmV 40.9 dB 5795568 0 0
11 Locked QAM256 10 525000000 Hz -4.5 dBmV 41.0 dB 5799348 0 0
12 Locked QAM256 11 531000000 Hz -4.6 dBmV 40.9 dB 5803365 0 0
13 Locked QAM256 12 537000000 Hz -4.7 dBmV 40.7 dB 5806888 0 0
14 Locked QAM256 13 543000000 Hz -4.8 dBmV 41.0 dB 5810756 0 0
15 Locked QAM256 14 549000000 Hz -4.9 dBmV 40.9 dB 5815014 0 0
16 Locked QAM256 15 555000000 Hz -4.8 dBmV 41.0 dB 5818324 0 0
17 Locked QAM256 16 561000000 Hz -4.6 dBmV 41.0 dB 5822075 0 0
18 Locked QAM256 17 567000000 Hz -4.8 dBmV 40.8 dB 5825895 0 0
19 Locked QAM256 18 573000000 Hz -5.3 dBmV 40.7 dB 5829683 0 0
20 Locked QAM256 19 579000000 Hz -5.8 dBmV 40.4 dB 5833236 0 0
21 Locked QAM256 20 585000000 Hz -6.1 dBmV 40.3 dB 5837655 0 0
22 Locked QAM256 21 591000000 Hz -6.1 dBmV 40.3 dB 5840900 0 0
23 Locked QAM256 22 597000000 Hz -6.1 dBmV 40.2 dB 5845010 0 0
24 Locked QAM256 24 609000000 Hz -6.3 dBmV 40.2 dB 5848496 0 0
25 Locked QAM256 25 615000000 Hz -6.6 dBmV 40.0 dB 5860728 0 0
26 Locked QAM256 26 621000000 Hz -6.7 dBmV 39.8 dB 5864665 0 0
27 Locked QAM256 27 627000000 Hz -6.6 dBmV 39.9 dB 5868124 0 0
28 Locked QAM256 29 639000000 Hz -5.9 dBmV 40.2 dB 5871948 0 0
29 Locked QAM256 30 645000000 Hz -5.8 dBmV 40.2 dB 5875815 0 0
30 Locked QAM256 31 651000000 Hz -6.6 dBmV 39.8 dB 5875132 0 0
31 Locked QAM256 32 657000000 Hz -7.4 dBmV 39.3 dB 5875750 0 0
32 Not Locked Unknown 0 0 Hz 0.0 dBmV 0.0 dB 0 0 0

<tabindex=-1>Upstream Bonded Channels</tabindex=-1>
Channel Lock Status Modulation Channel ID Frequency Power
1 Locked ATDMA 1 35800000 Hz 46.3 dBmV
2 Locked ATDMA 2 29400000 Hz 46.3 dBmV
3 Locked ATDMA 3 23000000 Hz 45.5 dBmV
4 Locked ATDMA 4 16600000 Hz 45.5 dBmV
5 Not Locked Unknown 0 0 Hz 0.0 dBmV
6 Not Locked Unknown 0 0 Hz 0.0 dBmV
7 Not Locked Unknown 0 0 Hz 0.0 dBmV
8 Not Locked Unknown 0 0 Hz 0.0 dBmV

<tabindex=-1>Downstream OFDM Channels</tabindex=-1>
Channel Lock Status Modulation / Profile ID Channel ID Frequency Power SNR / MER Active Subcarrier Number Range Unerrored Codewords Correctable Codewords Uncorrectable Codewords
1 Locked 0, 1, 255 33 690000000 Hz -6.3 dBmV 36.3 dB 1108 ~ 2987 11559629 11484045 0
2 Not Locked 0, 255 0 0 Hz -2.0 dBmV 0.0 dB 0 ~ 4095 0 0 0

<tabindex=-1>Upstream OFDMA Channels</tabindex=-1>
Channel Lock Status Modulation / Profile ID Channel ID Frequency Power
1 Not Locked Unknown 0 0 Hz 0 dBmV
2 Not Locked Unknown 0 0 Hz 0 dBmV

 


Contributor

Re: Tech Left and could not figure out the internet issue..

You posted partial downstream channel  information, if you have gigabit service then you are on a docsis 3.1 modem. . Please provide additional information,  modem model, upstream and downstream channel stats, and the event logs. You should also be aware that speedtest should be ran with a direct connection to the modem  not wifi. 

Expert

Re: Tech Left and could not figure out the internet issue..

The stats are ok albeit the downstream power is on the weak side. Please post the modem's error / event log entries as well.


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Re: Tech Left and could not figure out the internet issue..

Time
Priority
Description
2019-06-07, 17:42:34
Notice (6)
DS profile assignment change. DS Chan ID: 32; Previous Profile: ; New Profile: 1 .;CM-MAC=78:d2:94:61:f7:18;CMTS-MAC=00:01:5c:ae:ee:73;CM-QOS=1.1;CM-VER=3.1;
Time Not Established
Notice (6)
Honoring MDD; IP provisioning mode = IPv6
Time Not Established
Critical (3)
No Ranging Response received - T3 time-out;CM-MAC=78:d2:94:61:f7:18;CMTS-MAC=00:01:5c:ae:ee:73;CM-QOS=1.1;CM-VER=3.1;
Time Not Established
Critical (3)
SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CM-MAC=78:d2:94:61:f7:18;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;
Time Not Established
Critical (3)
No Ranging Response received - T3 time-out;CM-MAC=78:d2:94:61:f7:18;CMTS-MAC=00:01:5c:ae:ee:73;CM-QOS=1.1;CM-VER=3.1;
Time Not Established
Critical (3)
SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CM-MAC=78:d2:94:61:f7:18;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;
Time Not Established
Critical (3)
No Ranging Response received - T3 time-out;CM-MAC=78:d2:94:61:f7:18;CMTS-MAC=00:01:5c:ae:ee:73;CM-QOS=1.1;CM-VER=3.1;
Time Not Established
Critical (3)
SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CM-MAC=78:d2:94:61:f7:18;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;
Time Not Established
Critical (3)
No Ranging Response received - T3 time-out;CM-MAC=78:d2:94:61:f7:18;CMTS-MAC=00:01:5c:ae:ee:73;CM-QOS=1.1;CM-VER=3.1;
2019-06-07, 15:47:02
Critical (3)
SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CM-MAC=78:d2:94:61:f7:18;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;
2019-06-07, 15:46:57
Critical (3)
Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=78:d2:94:61:f7:18;CMTS-MAC=00:01:5c:ae:ee:73;CM-QOS=1.1;CM-VER=3.1;
2019-06-07, 15:46:57
Critical (3)
SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CM-MAC=78:d2:94:61:f7:18;CMTS-MAC=00:01:5c:ae:ee:73;CM-QOS=1.1;CM-VER=3.1;
2019-06-07, 15:46:56
Critical (3)
Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=78:d2:94:61:f7:18;CMTS-MAC=00:01:5c:ae:ee:73;CM-QOS=1.1;CM-VER=3.1;
2019-06-07, 15:46:56
Critical (3)
SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CM-MAC=78:d2:94:61:f7:18;CMTS-MAC=00:01:5c:ae:ee:73;CM-QOS=1.1;CM-VER=3.1;
2019-06-07, 15:46:56
Critical (3)
Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=78:d2:94:61:f7:18;CMTS-MAC=00:01:5c:ae:ee:73;CM-QOS=1.1;CM-VER=3.1;
2019-06-07, 15:44:15
Critical (3)
SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CM-MAC=78:d2:94:61:f7:18;CMTS-MAC=00:01:5c:ae:ee:73;CM-QOS=1.1;CM-VER=3.1;
2019-06-07, 15:44:09
Critical (3)
SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CM-MAC=78:d2:94:61:f7:18;CMTS-MAC=00:01:5c:ae:ee:73;CM-QOS=1.1;CM-VER=3.1;
2019-06-07, 15:44:06
Critical (3)
SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CM-MAC=78:d2:94:61:f7:18;CMTS-MAC=00:01:5c:ae:ee:73;CM-QOS=1.1;CM-VER=3.1;
Time Not Established
Critical (3)
SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CM-MAC=78:d2:94:61:f7:18;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;
Time Not Established
Critical (3)
No Ranging Response received - T3 time-out;CM-MAC=78:d2:94:61:f7:18;CMTS-MAC=00:01:5c:ae:ee:73;CM-QOS=1.1;CM-VER=3.1;
Time Not Established
Critical (3)
SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CM-MAC=78:d2:94:61:f7:18;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;
2019-06-06, 17:20:30
Critical (3)
Resetting the cable modem due to docsDevResetNow
Time Not Established
Critical (3)
No Ranging Response received - T3 time-out;CM-MAC=78:d2:94:61:f7:18;CMTS-MAC=00:01:5c:ae:ee:73;CM-QOS=1.1;CM-VER=3.1;
Time Not Established
Critical (3)
SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CM-MAC=78:d2:94:61:f7:18;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;
2019-06-06, 17:02:22
Critical (3)
Resetting the cable modem due to docsDevResetNow
Time Not Established
Critical (3)
SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CM-MAC=78:d2:94:61:f7:18;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;
Time Not Established
Critical (3)
No Ranging Response received - T3 time-out;CM-MAC=78:d2:94:61:f7:18;CMTS-MAC=00:01:5c:ae:ee:73;CM-QOS=1.1;CM-VER=3.1;
Time Not Established
Critical (3)
SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CM-MAC=78:d2:94:61:f7:18;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;
Time Not Established
Critical (3)
No Ranging Response received - T3 time-out;CM-MAC=78:d2:94:61:f7:18;CMTS-MAC=00:01:5c:ae:ee:73;CM-QOS=1.1;CM-VER=3.1;
Time Not Established
Critical (3)
SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CM-MAC=78:d2:94:61:f7:18;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;
Time Not Established
Critical (3)
No Ranging Response received - T3 time-out;CM-MAC=78:d2:94:61:f7:18;CMTS-MAC=00:01:5c:ae:ee:73;CM-QOS=1.1;CM-VER=3.1;
Time Not Established
Critical (3)
SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CM-MAC=78:d2:94:61:f7:18;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;
Time Not Established
Critical (3)
No Ranging Response received - T3 time-out;CM-MAC=78:d2:94:61:f7:18;CMTS-MAC=00:01:5c:ae:ee:73;CM-QOS=1.1;CM-VER=3.1;
Time Not Established
Critical (3)
SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CM-MAC=78:d2:94:61:f7:18;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;
2019-03-19, 10:04:57
Critical (3)
Resetting the cable modem due to docsDevResetNow
2019-03-18, 16:24:35
Critical (3)
No Ranging Response received - T3 time-out;CM-MAC=78:d2:94:61:f7:18;CMTS-MAC=00:01:5c:ae:ee:73;CM-QOS=1.1;CM-VER=3.1;
2019-03-18, 16:24:26
Critical (3)
DHCP failed - DHCP Solicit sent, No DHCP Advertise received;CM-MAC=78:d2:94:61:f7:18;CMTS-MAC=00:01:5c:ae:ee:73;CM-QOS=1.1;CM-VER=3.1;
2019-03-18, 16:23:43
Critical (3)
No Ranging Response received - T3 time-out;CM-MAC=78:d2:94:61:f7:18;CMTS-MAC=00:01:5c:ae:ee:73;CM-QOS=1.1;CM-VER=3.1;
Time Not Established
Critical (3)
No Ranging Response received - T3 time-out;CM-MAC=78:d2:94:61:f7:18;CMTS-MAC=00:01:5c:ae:ee:73;CM-QOS=1.1;CM-VER=3.1;
Time Not Established
Critical (3)
SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CM-MAC=78:d2:94:61:f7:18;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;

 

 

Frequent Visitor

Re: Tech Left and could not figure out the internet issue..

Netgear CM1000
Firmware version v3.01.06
yes, i am hardwared, i by passed my router totally also .

And yes i listed all of the downstream and upstream information above.. That is everything on the entire page.

This worked totally fine up too two weeks ago

I posted everything on my page above upstream OFDMA channels, Downstream OFDM channels, Upstream Bonded channels, Downstream bonded channels and startup procedure

Contributor

Re: Tech Left and could not figure out the internet issue..

The only thing visible in your post is the information for 16 downstream channels,  nothing for the upstream or ofdm.

Contributor

Re: Tech Left and could not figure out the internet issue..

Sorry, I see the rest now. Missed the scroll bars.

Frequent Visitor

Re: Tech Left and could not figure out the internet issue..

anymore information that i need to provide?

isnt suppose to says like DOCSIS 3.1 under provisioning mode or somthing?

Expert

Re: Tech Left and could not figure out the internet issue..


@Jbog2080 wrote:


isnt suppose to says like DOCSIS 3.1 under provisioning mode or somthing?


No. What it says is correct.

 

Even though the signal stats looked o/k at that snapshot in time, the error log entries confirm that something is going on. Perhaps there is noise ingress into the line(s) somewhere.


There are other signal stat figures that can't be read by the modem. They are the "Upstream Rx Power" (Upstream Receive Power Level), the "Upstream SNR Ch." (Upstream Signal To Noise Ratio), and the "Upstream ICFR" (In Channel Frequency Response). These are as equally important in diagnosing connectivity issues as are the modem's stats.


I'm going to escalate your issue to the Comcast corporate employees that are available to these boards. They can check the CMTS (Cable Modem Termination System) for any real time degradation and / or error reports, see your node / cable plant and modem health, and see whether or not everything is in the green zone. They can also see a history plot for the modem and poll for those upstream receive signal stats.

You should get a reply here in your topic. Good luck !



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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? Mark the post as Best Answer!
Frequent Visitor

Re: Tech Left and could not figure out the internet issue..

Thank you so much! Anything you guys need from me let me know!..

Official Employee

Re: Tech Left and could not figure out the internet issue..

Hey there, Jbog2080! Thank you for reaching out to us here on the forums. I get how important it is to ensure you're getting the speeds you're subscribed to! I would be happy to help review this further with you. To get started, can you please send me a PM with your first and last name? Thank you! 

To send me a Private Message, please click my name “ComcastAlly” and click “Send a message.”


I am an Official Comcast Employee.
Official Employees are from multiple teams within Comcast: CARE, Product, Leadership. We ask that you post publicly so people with similar questions may benefit from the conversation.
Was your question answered? Mark the post as Best Answer!
Frequent Visitor

Re: Tech Left and could not figure out the internet issue..

i PM'd you