Internet cuts out constantly

[anonymous9]

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	2	4	3	1
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

[EG]

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 !

[anonymous9]

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.