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Daily connection loss

jmag2013
New Poster

Daily connection loss

For the past couple of months, my connection keeps dropping about once per day. My modem will lose connection and then upon trying to reconnect, it will hang while it's looking for an upstream signal.

I talked to XFinity support about a month ago and initially they told me that my upstream signal is low, and that the Advanced Repair Team will give me a call in a couple of days. They never did. The problem persisted, so I spoke to support again yesterday and this time they told me that everything looked good in terms of signal power. The thing the rep did find is that my download speed is about 1/6th of what it should be.

 

Modem: Netgear CM1000, which is 2 months old

Router: tp-link Archer A7

 

Relevant event Log:

2020-05-27, 09:56:04 Notice (6) DS profile assignment change. DS Chan ID: 32; Previous Profile: ; New Profile: 1.;CM-MAC=;CM-VER=3.1;
Time Not Established Notice (6) Honoring MDD; IP provisioning mode = IPv6
Time Not Established Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CM-MAC=;CMTS-MAC=CM-QOS=1.1;CM-VER=3.1;
2020-05-27, 09:53:04 Critical (3) Unicast Ranging Received Abort Response - Re-initializing MAC;CM-MAC=;CMTS-MAC=00:90:f0:4a:00:00;CM-QOS=1.1;CM-VER=3.1;
2020-05-27, 09:52:55 Critical (3) Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=;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=;CM-QOS=1.1;CM-VER=3.1;
2020-05-27, 06:22:31 Critical (3) Unicast Ranging Received Abort Response - Re-initializing MAC;CM-MAC=38:94:ed:73:5a:48;CMTS-MAC=;CM-QOS=1.1;CM-VER=3.1;
2020-05-27, 06:22:22 Critical (3) No Ranging Response received - T3 time-out;CM-MAC=;CM-QOS=1.1;CM-VER=3.1;
2020-05-27, 06:20:25 Critical (3) Unicast Ranging Received Abort Response - Re-initializing MAC;CM-MAC=;CM-QOS=1.1;CM-VER=3.1;
2020-05-27, 06:19:57 Critical (3) No Ranging Response received - T3 time-out;CM-MAC=;CM-QOS=1.1;CM-VER=3.1;
2020-05-27, 06:18:47 Critical (3) Unicast Ranging Received Abort Response - Re-initializing MAC;CM-MAC=;CM-QOS=1.1;CM-VER=3.1;
2020-05-27, 06:16:22 Critical (3)

SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CM-MAC=;CM-QOS=1.1;CM-VER=3.1;

 

 

<tabindex=-1>Upstream Bonded Channels</tabindex=-1>
Channel Lock Status Modulation Channel ID Frequency Power
1 Locked ATDMA 1 38800000 Hz 51.5 dBmV
2 Locked ATDMA 2 32400000 Hz 51.3 dBmV
3 Locked ATDMA 3 26000000 Hz 50.8 dBmV
4 Locked ATDMA 4 19600000 Hz 50.3 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 Bonded Channels</tabindex=-1>
Channel Lock Status Modulation Channel ID Frequency Power SNR / MER Unerrored Codewords Correctable Codewords Uncorrectable Codewords
1 Locked QAM256 17 585000000 Hz -6.5 dBmV 43.9 dB 15232599 0 0
2 Locked QAM256 1 489000000 Hz -7.0 dBmV 44.0 dB 11953800 0 0
3 Locked QAM256 2 495000000 Hz -7.0 dBmV 43.9 dB 11957895 0 0
4 Locked QAM256 3 501000000 Hz -6.8 dBmV 43.8 dB 11961553 0 0
5 Locked QAM256 4 507000000 Hz -6.8 dBmV 43.9 dB 11964919 0 0
6 Locked QAM256 5 513000000 Hz -6.6 dBmV 44.1 dB 11968789 0 0
7 Locked QAM256 6 519000000 Hz -6.7 dBmV 44.0 dB 11972616 0 0
8 Locked QAM256 7 525000000 Hz -6.6 dBmV 44.1 dB 11976664 0 0
9 Locked QAM256 8 531000000 Hz -6.9 dBmV 43.9 dB 11980521 0 0
10 Locked QAM256 9 537000000 Hz -6.6 dBmV 44.1 dB 11984136 0 0
11 Locked QAM256 10 543000000 Hz -7.0 dBmV 43.6 dB 11987635 0 0
12 Locked QAM256 11 549000000 Hz -6.8 dBmV 43.9 dB 11991631 0 0
13 Locked QAM256 12 555000000 Hz -6.8 dBmV 44.0 dB 11995255 0 0
14 Locked QAM256 13 561000000 Hz -6.8 dBmV 43.9 dB 11999129 0 0
15 Locked QAM256 14 567000000 Hz -6.8 dBmV 43.8 dB 12002964 0 0
16 Locked QAM256 15 573000000 Hz -6.5 dBmV 44.0 dB 12006947 0 0
17 Locked QAM256 16 579000000 Hz -6.7 dBmV 43.9 dB 12010810 0 0
18 Locked QAM256 18 591000000 Hz -6.6 dBmV 43.9 dB 12014245 0 0
19 Locked QAM256 19 597000000 Hz -6.5 dBmV 43.9 dB 12018064 0 0
20 Locked QAM256 20 603000000 Hz -6.4 dBmV 43.8 dB 12021677 0 0
21 Locked QAM256 21 609000000 Hz -6.7 dBmV 43.7 dB 12025644 0 0
22 Locked QAM256 22 615000000 Hz -6.8 dBmV 43.7 dB 12029317 0 0
23 Locked QAM256 23 621000000 Hz -6.8 dBmV 43.5 dB 12032934 0 0
24 Locked QAM256 24 627000000 Hz -6.7 dBmV 43.8 dB 12036806 0 0
25 Locked QAM256 25 633000000 Hz -7.1 dBmV 43.4 dB 12040347 0 0
26 Locked QAM256 26 639000000 Hz -6.7 dBmV 43.7 dB 12044181 0 0
27 Locked QAM256 27 645000000 Hz -7.3 dBmV 43.2 dB 12048023 0 0
28 Locked QAM256 28 651000000 Hz -6.9 dBmV 43.5 dB 12051491 0 0
29 Locked QAM256 29 657000000 Hz -7.5 dBmV 43.0 dB 12055578 0 0
30 Locked QAM256 30 663000000 Hz -7.5 dBmV 43.1 dB 12057422 0 0
31 Locked QAM256 31 669000000 Hz -7.3 dBmV 43.2 dB 12058638 0 0
32 Locked QAM256 32 675000000 Hz -7.5 dBmV 41.7 dB 12059346 0 0

 

 

 

 

 

 

EG
Expert

Re: Daily connection loss

The upstream power is too high 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, and latency problems.

In a self troubleshooting 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 5-1002 MHz, bi-directional, and no gold colored garbage types like GE, RadioShack, RCA, Philips, Leviton, Magnavox, and Rocketfish from big box stores like Home Depot, Lowes, Target, Wal-Mart etc. Splitters should be swapped with known to be good / new ones to test

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.



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jmag2013
New Poster

Re: Daily connection loss

Thanks a lot. That's what I thought, but I'm somewhat ignorant with the low-level netorking stuff.

 

I have no splitters in my house, nor anywhere else, to my knowledge. Like I said, though, when the rep checked my signal, everything was green. I'll reach out to them again and see if I can have a tech come out.  

EG
Expert

Re: Daily connection loss

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.

Good luck with it !



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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!