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Help! Multiple disconnects and need to power cycle modem multiple times per week

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Help! Multiple disconnects and need to power cycle modem multiple times per week

Can I have the community review my modem specs and let me know what may be the issue and a process for resolution. The below screenshots are approximately 1 hour after a factory modem reset. Thanks for your help!

 

I am using an MB8600 modem

 

Downtstream:

Channel Lock Status Modulation Channel ID Freq. (MHz) Pwr (dBmV) SNR (dB.) Corrected Uncorrected
   1 Locked QAM256 13 555 -4.7 39 0 0
   2 Locked QAM256 1 477 -3.8 39.7 0 0
   3 Locked QAM256 2 483 -3.8 39.7 0 0
   4 Locked QAM256 3 489 -3.9 39.6 0 0
   5 Locked QAM256 4 495 -4.1 39.3 0 0
   6 Locked QAM256 5 507 -4.2 39.4 0 0
   7 Locked QAM256 6 513 -4.8 39.2 0 0
   8 Locked QAM256 7 519 -4.3 39.3 0 0
   9 Locked QAM256 8 525 -4.5 39 0 0
   10 Locked QAM256 9 531 -4.8 39 0 0
   11 Locked QAM256 10 537 -4.7 38.9 0 0
   12 Locked QAM256 11 543 -4.5 39.1 0 0
   13 Locked QAM256 12 549 -5.1 39 0 0
   14 Locked QAM256 14 561 -4.6 39.1 0 0
   15 Locked QAM256 15 567 -4.2 39.3 0 0
   16 Locked QAM256 16 573 -4.2 39.1 0 0
   17 Locked QAM256 17 579 -4.1 39.3 0 0
   18 Locked QAM256 18 585 -3.2 39.5 0 0
   19 Locked QAM256 19 591 -3.4 39.3 0 0
   20 Locked QAM256 20 597 -3.2 39.3 0 0
   21 Locked QAM256 21 603 -2.8 39.5 0 0
   22 Locked QAM256 22 609 -3.2 39.3 0 0
   23 Locked QAM256 23 615 -3.3 39.4 0 0
   24 Locked QAM256 24 621 -2.9 39.4 0 0
   25 Locked QAM256 25 627 -2.9 39.3 0 0
   26 Locked QAM256 26 633 -2.8 39.3 0 0
   27 Locked QAM256 27 639 -3.1 39.2 0 0
   28 Locked QAM256 28 645 -2.6 39.4 0 0
   29 Locked QAM256 29 651 -2.7 39.3 0 0
   30 Locked QAM256 30 657 -2.7 39.2 0 0
   31 Locked QAM256 31 663 -2.6 39.3 0 0
   32 Locked QAM256 32 669 -2.5 39.3 0 0
   33 Locked OFDM PLC 159 678 -1.2 15.2 6077944 0

 

Upstream:

Channel Lock Status Channel Type Channel ID Symb. Rate (Ksym/sec) Freq. (MHz) Pwr (dBmV)
   1 Locked SC-QAM 5 5120 36.5 50
   2 Locked SC-QAM 6 5120 30.1 50.5
   3 Locked SC-QAM 7 5120 23.7 50

 

Log:

Time Priority Description
Time Not Established Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=00:40:36:4e:80:99;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;
Time Not Established Warning (5) Lost MDD Timeout;CM-MAC=00:40:36:4e:80:99;CMTS-MAC=00:00:00:00:00:00;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=00:40:36:4e:80:99;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;
Time Not Established Warning (5) Lost MDD Timeout;CM-MAC=00:40:36:4e:80:99;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=00:40:36:4e:80:99;CMTS-MAC=dc:eb:94:b4:1e:43;CM-QOS=1.1;CM-VER=3.1;
Time Not Established Notice (6) Honoring MDD; IP provisioning mode = IPv6
08:50:59
Sun Aug 18 2019
Warning (5) RNG-RSP CCAP Commanded Power Exceeds Value Corresponding to the Top of the DRW;CM-MAC=00:40:36:4e:80:99;CMTS-MAC=dc:eb:94:b4:1e:43;CM-QOS=1.1;CM-VER=3.1;
08:50:59
Sun Aug 18 2019
Warning (5) Dynamic Range Window violation
08:52:39
Sun Aug 18 2019
Warning (5) RNG-RSP CCAP Commanded Power Exceeds Value Corresponding to the Top of the DRW;CM-MAC=00:40:36:4e:80:99;CMTS-MAC=dc:eb:94:b4:1e:43;CM-QOS=1.1;CM-VER=3.1;
08:52:39
Sun Aug 18 2019
Warning (5) Dynamic Range Window violation
08:53:26
Sun Aug 18 2019
Critical (3) SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=00:40:36:4e:80:99;CMTS-MAC=dc:eb:94:b4:1e:43;CM-QOS=1.1;CM-VER=3.1;
09:10:29
Sun Aug 18 2019
Warning (5) RNG-RSP CCAP Commanded Power Exceeds Value Corresponding to the Top of the DRW;CM-MAC=00:40:36:4e:80:99;CMTS-MAC=dc:eb:94:b4:1e:43;CM-QOS=1.1;CM-VER=3.1;
09:10:29
Sun Aug 18 2019
Warning (5) Dynamic Range Window violation
09:29:47
Sun Aug 18 2019
Warning (5) RNG-RSP CCAP Commanded Power Exceeds Value Corresponding to the Top of the DRW;CM-MAC=00:40:36:4e:80:99;CMTS-MAC=dc:eb:94:b4:1e:43;CM-QOS=1.1;CM-VER=3.1;
09:29:47
Sun Aug 18 2019
Warning (5) Dynamic Range Window violation
09:49:45
Sun Aug 18 2019
Warning (5) RNG-RSP CCAP Commanded Power Exceeds Value Corresponding to the Top of the DRW;CM-MAC=00:40:36:4e:80:99;CMTS-MAC=dc:eb:94:b4:1e:43;CM-QOS=1.1;CM-VER=3.1;
09:49:45
Sun Aug 18 2019
Warning (5) Dynamic Range Window violation

 

 

Highlighted
Gold Problem Solver

Re: Help! Multiple disconnects and need to power cycle modem multiple times per week

The downstream signals look OK, but the upstream levels are borderline/too high. And the error log "Dynamic Range Window" and "Commanded Power Exceeds" errors both suggest an intermittent connection to Comcast's network affecting the upstream channels.

 

If you want to troubleshoot this yourself, please see Connection Troubleshooting Tips. Problems with Internet service are often due to poor connections between your equipment and Comcast's network, usually in or near your home.

If you can't find the problem or you'd rather have Comcast do the troubleshooting, call them at the phone number on your bill or 1-800-Comcast, or or use one of the options on https://www.xfinity.com/support/contact-us/. It isn't likely they can fix this remotely, and if not insist they send a tech out to identify the cause and correct it.

If the tech finds bad coax, splitters, amplifiers, or connections in your home (even if Comcast originally supplied them) you'll probably have to pay for the visit unless you have their Service Protection Plan (https://www.xfinity.com/support/articles/service-protection-plan, closed to customers that don't already have it). If the trouble is due to a faulty Comcast rental device, or anything outside your home, you shouldn't be charged.