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Internet cuts out constantly

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Regular Visitor

Internet cuts out constantly

My internet cuts out constantly. I have called Comcast Xfinity over 15 times in the past month about this issue and have had three technicians visit recently (including two in the past 1-2 weeks). Both times, the technicians thought they had identified and fixed the problem. However, the problem persists. I have wasted countless hours on the phone with customer service, going through the same steps, over and over and over.

 

Comcast customer service has been very unhelpful (however, the technicians who have visited have all been great). They say they cannot schedule another visit because it is an "internal" issue - however, the last technician who visited measured the signal *inside* my house and didn't find any problems. Instead, he said that Comcast made an error when our neighbors (who just moved in) recently connected their cable TV. Every time I call customer service, it is a different story.

 

Anyway, I thought I would try to debug the problem here. If anyone can help at all, I would really appreciate it. I will copy my modem log below, but if there's anything else that would be useful, please let me know. We also purchased a new wireless router, but this didn't fix the problem. Thank you.

 

May 22 2020 00:10:33 3-Critical R02.0 No Ranging Response received - T3 time-out;CM-MAC=20:3d:66:05:25:77;CMTS-MAC=00:87:31:90:0a:3f;CM-QOS=1.1;CM-VER=3.0;
May 22 2020 00:10:22 3-Critical R07.0 Unicast Ranging Received Abort Response - initializing MAC;CM-MAC=20:3d:66:05:25:77;CMTS-MAC=00:87:31:90:0a:3f;CM-QOS=1.1;CM-VER=3.0;
May 22 2020 00:06:31 3-Critical R02.0 No Ranging Response received - T3 time-out;CM-MAC=20:3d:66:05:25:77;CMTS-MAC=00:87:31:90:0a:3f;CM-QOS=1.1;CM-VER=3.0;
May 21 2020 23:18:49 3-Critical R07.0 Unicast Ranging Received Abort Response - initializing MAC;CM-MAC=20:3d:66:05:25:77;CMTS-MAC=00:87:31:90:0a:3f;CM-QOS=1.1;CM-VER=3.0;
May 21 2020 23:18:29 3-Critical R02.0 No Ranging Response received - T3 time-out;CM-MAC=20:3d:66:05:25:77;CMTS-MAC=00:87:31:90:0a:3f;CM-QOS=1.1;CM-VER=3.0;
May 21 2020 23:18:29 3-Critical R07.0 Unicast Ranging Received Abort Response - initializing MAC;CM-MAC=20:3d:66:05:25:77;CMTS-MAC=00:87:31:90:0a:3f;CM-QOS=1.1;CM-VER=3.0;
May 21 2020 23:17:34 3-Critical R02.0 No Ranging Response received - T3 time-out;CM-MAC=20:3d:66:05:25:77;CMTS-MAC=00:87:31:90:0a:3f;CM-QOS=1.1;CM-VER=3.0;
May 21 2020 23:17:29 3-Critical R07.0 Unicast Ranging Received Abort Response - initializing MAC;CM-MAC=20:3d:66:05:25:77;CMTS-MAC=00:87:31:90:0a:3f;CM-QOS=1.1;CM-VER=3.0;
May 21 2020 23:04:15 3-Critical R02.0 No Ranging Response received - T3 time-out;CM-MAC=20:3d:66:05:25:77;CMTS-MAC=00:87:31:90:0a:3f;CM-QOS=1.1;CM-VER=3.0;
May 21 2020 23:04:10 3-Critical R07.0 Unicast Ranging Received Abort Response - initializing MAC;CM-MAC=20:3d:66:05:25:77;CMTS-MAC=00:87:31:90:0a:3f;CM-QOS=1.1;CM-VER=3.0;
May 21 2020 23:03:56 3-Critical R02.0 No Ranging Response received - T3 time-out;CM-MAC=20:3d:66:05:25:77;CMTS-MAC=00:87:31:90:0a:3f;CM-QOS=1.1;CM-VER=3.0;
May 21 2020 23:03:56 3-Critical R07.0 Unicast Ranging Received Abort Response - initializing MAC;CM-MAC=20:3d:66:05:25:77;CMTS-MAC=00:87:31:90:0a:3f;CM-QOS=1.1;CM-VER=3.0;
May 21 2020 23:03:43 3-Critical R02.0 No Ranging Response received - T3 time-out;CM-MAC=20:3d:66:05:25:77;CMTS-MAC=00:87:31:90:0a:3f;CM-QOS=1.1;CM-VER=3.0;
May 21 2020 18:50:39 5-Warning Z00.0 MIMO Event MIMO: Stored MIMO=-1 post cfg file MIMO=-1;CM-MAC=20:3d:66:05:25:77;CMTS-MAC=00:87:31:90:0a:3f;CM-QOS=1.1;CM-VER=3.0;
Jan 01 1970 00:00:22 3-Critical R02.0 No Ranging Response received - T3 time-out;CM-MAC=20:3d:66:05:25:77;CMTS-MAC=00:87:31:90:0a:3f;CM-QOS=1.1;CM-VER=3.0;
Jan 01 1970 00:00:18 6-Notice N/A Cable Modem Reboot due to power reset ;CM-MAC=20:3d:66:05:25:77;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.0;
May 21 2020 18:46:44 3-Critical R02.0 No Ranging Response received - T3 time-out;CM-MAC=20:3d:66:05:25:77;CMTS-MAC=00:87:31:90:0a:3f;CM-QOS=1.1;CM-VER=3.0;
May 21 2020 18:46:24 3-Critical R07.0 Unicast Ranging Received Abort Response - initializing MAC;CM-MAC=20:3d:66:05:25:77;CMTS-MAC=00:87:31:90:0a:3f;CM-QOS=1.1;CM-VER=3.0;
May 21 2020 18:36:35 3-Critical R02.0 No Ranging Response received - T3 time-out;CM-MAC=20:3d:66:05:25:77;CMTS-MAC=00:87:31:90:0a:3f;CM-QOS=1.1;CM-VER=3.0;
May 21 2020 18:35:25 3-Critical R07.0 Unicast Ranging Received Abort Response - initializing MAC;CM-MAC=20:3d:66:05:25:77;CMTS-MAC=00:87:31:90:0a:3f;CM-QOS=1.1;CM-VER=3.0;

 

Here is my signal information:

 

Downstream Bonding Channel Value
Channel ID 33  34  35  36  37  38  39  40 
Frequency 651000000 Hz  657000000 Hz  663000000 Hz  669000000 Hz  675000000 Hz  681000000 Hz  687000000 Hz  693000000 Hz 
Signal to Noise Ratio 35 dB  35 dB  35 dB  34 dB  33 dB  32 dB  33 dB  34 dB 
Downstream Modulation QAM256  QAM256  QAM256  QAM256  QAM256  QAM256  QAM256  QAM256 
Power Level
The Downstream Power Level reading is a snapshot taken at the time this page was requested. Please Reload/Refresh this Page for a new reading
-11 dBmV   -11 dBmV   -11 dBmV   -13 dBmV   -14 dBmV   -15 dBmV   -14 dBmV  

-14 dBmV  

 

 

 

Upstream Bonding Channel Value
Channel ID
Frequency 30100000 Hz  17300000 Hz  23700000 Hz  36500000 Hz 
Ranging Service ID 598  598  598  598 
Symbol Rate 5.120 Msym/sec  5.120 Msym/sec  5.120 Msym/sec  5.120 Msym/sec 
Power Level 47 dBmV  49 dBmV  49 dBmV  47 dBmV 
Upstream Modulation [2] QPSK
[1] 16QAM
[3] 64QAM
 
[2] QPSK
[1] 16QAM
[3] 64QAM
 
[2] QPSK
[1] 16QAM
[3] 64QAM
 
[2] QPSK
[1] 16QAM
[3] 64QAM
 
Ranging Status Success  Success  Success  Success 

 

 

Signal Status (Codewords) Bonding Channel Value
Channel ID 33  34  35  36  37  38  39  40 
Total Unerrored Codewords 1079451742  1078257584  1078221846  1078220988  1078180931  1078204285  1078251527  1078250466 
Total Correctable Codewords 3029  5771  6324  8403  9739  6576  787  1685 
Total Uncorrectable Codewords 12392  27251  33863  53163  69066  47620  3851  7646 

 

 

 

Highlighted
Expert

Re: Internet cuts out constantly

The downstream power is too low /out of spec as are the SNR's. 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 it's best to get the techs re-involved.

 

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 !




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Regular Visitor

Re: Internet cuts out constantly

Thank you very much.

 

Do you have any advice for getting through Comcast Customer Service? They are refusing to look at it or to send additional technicians.