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Visitor

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5 Messages

Wed, Nov 23, 2022 2:14 PM

Internet: Sync timing and critical 3 timeouts

Hi,

My internet cuts out for two minutes at a time multiple times a day.  I reached out to Motorola - I have a Motorola modem -  and sent them my logs and this was their reply:

Jillian here from Motorola Technical Support. I am happy to help. Thank you for sending over your Event log and connection page. 
 
I see you have quite a few Sync Timing Failures and Critical T3 Timeouts. I recommend reaching out to your ISP and having them send a tech out to get this fixed for you. Here is a bit more information on T3 timeouts for your convenience.
 
The cable modem has sent 16 ranging requests without receiving a ranging response reply from the provider. The cable modem is, therefore, resetting itself and restarting the registration process to the service provider.
 
This is normally caused by noise on the upstream side and can make it so the modem's power level is not sufficient enough to transmit messages. The inability to transmit messages within the timeout period will trigger the reset and restart the registration process. A T4 timeout is a more extreme version of a T3 error.
 
Generally, this indicates an occasional, temporary loss of service, but if the problem persists and is increases in frequency, it likely points to a larger issue with the condition of the coaxial network outside of the home, the cabling outside of the home that will need to be addressed by the service provider.

EG

Expert

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96.8K Messages

7 days ago

What do the modem's signal stats look like ? 

Please copy all of the text in its entirety of the *Downstream Power Levels*, the *SNR's* (Signal to Noise Ratios), and the *Upstream Power Level* numbers and paste them into your next post.


What is the exact model number of the Motorola modem ?

Please also post those RF error log entries in their entirety (copy and paste them, don't post a screenshot) but redact the CM MAC and the CMTS MAC addresses for your privacy. They are considered to be personal information. The posting of personally identifying information is a violation of their forum guidelines. The forum bot will not allow your post to be seen publically.

(edited)

Visitor

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2 Messages

@EG​ 

Hi,

It's a DOCSIS 3.1 (2.5 Gbps Ehternet Port)

Here's the event log with the Mac address redacted.  I just had it fail again a few minutes ago (It consistently fails a few times a day and is off for two minutes at a time:

Time    Priority    Description 
    Time Not Established   Critical (3)   No Ranging Response received - T3 time-out;CM-
    Time Not Established   Critical (3)   SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-
    Time Not Established   Critical (3)   No Ranging Response received - T3 time-out;CM-
    Time Not Established   Critical (3)   SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-
    Time Not Established   Critical (3)   No Ranging Response received - T3 time-out;CM-
    Time Not Established   Critical (3)   SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-
    Time Not Established   Critical (3)   No Ranging Response received - T3 time-out;CM-
    Time Not Established   Critical (3)   SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-
    Time Not Established   Critical (3)   No Ranging Response received - T3 time-out;CM-
    Time Not Established   Critical (3)   SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-
    Time Not Established   Critical (3)   No Ranging Response received - T3 time-out;CM-
    Time Not Established   Critical (3)   SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-
    Time Not Established   Critical (3)   No Ranging Response received - T3 time-out;CM-
    Time Not Established   Critical (3)   SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-
    Time Not Established   Critical (3)   No Ranging Response received - T3 time-out;CM-
    Time Not Established   Critical (3)   SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-
    Time Not Established   Critical (3)   No Ranging Response received - T3 time-out;CM-
    Time Not Established   Critical (3)   SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-
    Time Not Established   Critical (3)   No Ranging Response received - T3 time-out;CM-
    Time Not Established   Critical (3)   SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-QOS=1.1;CM-VER=3.1;
    Time Not Established   Critical (3)   No Ranging Response received - T3 time-out;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-QOS=1.1;CM-VER=3.1;
    Time Not Established   Critical (3)   No Ranging Response received - T3 time-out;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-QOS=1.1;CM-VER=3.1;
    Time Not Established   Critical (3)   No Ranging Response received - T3 time-out;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-QOS=1.1;CM-VER=3.1;
    Time Not Established   Critical (3)   No Ranging Response received - T3 time-out;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-QOS=1.1;CM-VER=3.1;
    Time Not Established   Critical (3)   No Ranging Response received - T3 time-out;CM-QOS=1.1;CM-VER=3.1;
    Time Not Established   Notice (6)   Honoring MDD; IP provisioning mode = IPv6
    21:15:06
Wed Nov 23 2022
  Notice (6)   DS profile assignment change. DS Chan ID: 32; Previous Profile: ; New Profile: 1 2 3.;CM-QOS=1.1;CM-VER=3.1;
    21:15:23
Wed Nov 23 2022
  Notice (6)   CM-STATUS message sent. Event Type Code: 24; Chan ID: 37; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: 0.;CM-QOS=1.1;CM-VER=3.1;

Visitor

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2 Messages

@EG​ 

FYI - User name is different because it's different logins for the same Xfinity account

As for the:

*Downstream Power Levels*, the *SNR's* (Signal to Noise Ratios), and the *Upstream Power Level*

I think this is everything:

Connection
   Startup Sequence    
   Startup Step Status Comment

  
   Acquire Downstream Channel 507000000 Hz Locked
  
   Upstream Connection OK Operational
  
   Boot State OK Operational

  
   Configuration File OK
  
   Security Enabled BPI+
  


   Connection Status    
   System Up Time 0 days 00h:23m:16s  
  
   Network Access Allowed  
  


   Downstream Bonded Channels  
  
   Channel Lock Status Modulation Channel ID Freq. (MHz) Pwr (dBmV) SNR (dB) Corrected Uncorrected
   1 Locked QAM256 9 507.0 -2.8 38.2 1 0
   2 Locked QAM256 6 489.0 -2.3 38.3 1 0
   3 Locked QAM256 7 495.0 -2.3 38.3 2 0
   4 Locked QAM256 8 501.0 -2.7 38.3 4 0
   5 Locked QAM256 10 513.0 -3.2 38.2 1 0
   6 Locked QAM256 11 519.0 -2.9 38.2 1 0
   7 Locked QAM256 12 525.0 -3.1 38.1 1 0
   8 Locked QAM256 13 531.0 -3.4 38.0 2 0
   9 Locked QAM256 14 537.0 -3.7 37.8 4 0
   10 Locked QAM256 15 543.0 -3.5 37.9 2 0
   11 Locked QAM256 16 549.0 -3.5 37.9 1 0
   12 Locked QAM256 17 555.0 -3.3 38.0 7 0
   13 Locked QAM256 18 561.0 -3.2 38.0 2 0
   14 Locked QAM256 19 567.0 -3.2 37.9 2 0
   15 Locked QAM256 20 573.0 -3.0 37.9 3 0
   16 Locked QAM256 21 579.0 -3.1 37.8 7 0
   17 Locked QAM256 22 585.0 -2.8 37.7 5 0
   18 Locked QAM256 23 591.0 -2.8 37.8 3 0
   19 Locked QAM256 24 597.0 -2.6 37.7 10 0
   20 Locked QAM256 25 603.0 -2.8 37.7 4 0
   21 Locked QAM256 26 609.0 -2.5 37.9 4 0
   22 Locked QAM256 27 615.0 -2.6 37.7 9 0
   23 Locked QAM256 28 621.0 -2.4 37.8 4 0
   24 Locked QAM256 29 627.0 -2.9 37.6 3 0
   25 Locked QAM256 30 633.0 -2.9 37.7 9 0
   26 Locked QAM256 31 639.0 -3.0 37.7 1 0
   27 Locked QAM256 32 645.0 -2.6 38.0 1 0
   28 Locked QAM256 33 651.0 -3.0 37.8 2 0
   29 Locked QAM256 34 657.0 -3.1 37.9 2 0
   30 Locked QAM256 35 663.0 -3.1 37.8 4 0
   31 Locked QAM256 36 669.0 -3.5 37.7 3 0
   32 Locked OFDM PLC 37 722.0 -3.4 37.1 18909835 0


   Upstream Bonded Channels  
  
   Channel Lock Status Channel Type Channel ID Symb. Rate (Ksym/sec) Freq. (MHz) Pwr (dBmV)
   1 Locked SC-QAM 1 5120 35.6 48.8
   2 Locked SC-QAM 2 5120 29.2 48.0
   3 Locked SC-QAM 3 5120 22.8 48.3
   4 Locked SC-QAM 4 5120 16.4 48.5
   5 Locked SC-QAM 9 2560 40.4 48.0

Is this everything you needed?

Thanks

 

Visitor

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5 Messages

After showing this log to someone in my IT department, they agreed with the person from Motorola - that someone from Xfinity needs to come out.

Official Employee

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321 Messages

Thank you for taking the time to reach out, @user_35d73e. I just wanted to reach out and check in on how things are going, were you able to use the option to send one of our experts a Direct Message so that we can get this looked into?

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
EG

Expert

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96.8K Messages

6 days ago

The upstream power is on the high side and it may be intermittently fluctuating even higher to out of spec levels. The downstream power is a bit on the weak side as well. That can cause random disconnects, spontaneous re-booting of the modem, speed, packet loss, latency problems, and the un-bonding of channels.

In an effort to try to obtain better connectivity / more wiggle room, check to see if there are there any excess/unneeded coax cable splitters in the line leading to the modem that can be eliminated/re-configured. Any splitters that remain should be high quality and cable rated for 5-1000 MHz, bi-directional, and no gold colored garbage from Radio Shack, Home Depot, Target, etc. Splitters should be swapped with known to be good / new ones to test.

Also check the coax cable for any damage such as cuts, nicks, abrasions, kinks, sharp bends, etc.

If there aren't any unneeded splitters that can be eliminated and if your coax wiring setup can't be reconfigured so that there is a single two-way splitter connected directly off of the drop from the street / pole with one port feeding the modem and the other port feeding the rest of the house/equipment with additional splits as needed and you've checked all the wiring and fittings for integrity and tightness and refresh them by taking them apart then check for and clean off any corrosion / oxidation on the center wire and put them back together again, then perhaps it's best to book a tech visit to investigate and correct.


Good luck with it !

EG

Expert

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96.8K Messages

6 days ago

@user_cae447 

If there is nothing that you can do to improve the connection quality, then yes, you'll need a tech visit as stated. 


Bear in mind that if the premises facing techs can not find or fix a problem at your home, it is they who are responsible for escalating it to their line / network / maintenance dept. techs. The problem may lie beyond your home in the local neighborhood infrastructure somewhere but it is their S.O.P. to start at the home. And if the problem is found to be on their side of the demarcation point, there will not be any charge.

(edited)

Visitor

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5 Messages

@EG​ 

Hi,

I checked all my connections and showed my stats to someone in my IT department at work and he agreed with your conclusion that Xfinity should come out to figure out what’s wrong with the line.  My wife and I work at home part time, so this is problematic. 

#Xfinity - can someone reach out ASAP?

Official Employee

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168 Messages

Hello, @user_cae447. Could you please send our team a direct message with your full name and full address? Our team can most definitely take a further look at this issue.
•  Make sure you are signed in here in the Xfinity Forum. Click "Sign In" if necessary 
•  Click the "Direct Message" icon (square chat icon in the upper right corner of your screen next to the bell icon) 
•  Click the "New message" (pencil and paper) icon 
•  Type "Xfinity Support" in the "To:" line and select "Xfinity Support" from the drop-down list which appears. The "Xfinity Support" graphic replaces the "To:" line 
•  Type your message in the text area near the bottom of the window 
•  Press Enter to send it

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
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