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Modem constantly keeps resetting

New Poster

Modem constantly keeps resetting

This issue started several weeks ago and I thought maybe I just needed a new modem. So I bought a new one and the problem is even worse. Internet will only stay connected for 15 minutes or so at a time and then disconnect.  I have to restart my modem to get it to reconnect and a few minutes later it disconnects again.  Just unplugging and replugging the modem doesn't work.  I have to unscrew the coax cable and unplug it, then put them back on to get it to connect.  I've replaced the coax cable and this is the only port in the house that we use.  I'm at my wits end. Help!!

Expert

Re: Modem constantly keeps resetting

What do the modem's signal stats look like ? Try getting them here http://192.168.100.1 or here http://10.0.0.1

Please post the *Downstream Power Level*, the *Upstream Power Level*, and the *SNR* (Signal to Noise Ratio) numbers.





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New Poster

Re: Modem constantly keeps resetting

Upstream Bonded Channels  
Channel Channel ID Lock Status US Channel Type Frequency Width Power  
1 2 Locked SC-QAM Upstream 29400000 Hz 6400000 Hz 58.0 dBmV  
2 1 Locked SC-QAM Upstream 35800000 Hz 6400000 Hz 58.0 dBmV  
3 3 Locked SC-QAM Upstream 23000000 Hz 6400000 Hz

58.0 dBmV

 

 

 
Downstream Bonded Channels
Channel ID Lock Status Modulation Frequency Power SNR/MER Corrected Uncorrectables
26 Locked QAM256 615000000 Hz -5.9 dBmV 39.3 dB 0 0
1 Locked QAM256 459000000 Hz -4.3 dBmV 40.2 dB 0 0
2 Locked QAM256 465000000 Hz -4.8 dBmV 40.3 dB 0 0
3 Locked QAM256 471000000 Hz -5.2 dBmV 40.1 dB 0 0
4 Locked QAM256 477000000 Hz -5.4 dBmV 40.0 dB 0 0
5 Locked QAM256 483000000 Hz -5.4 dBmV 40.0 dB 0 0
6 Locked QAM256 489000000 Hz -5.2 dBmV 39.9 dB 0 0
7 Locked QAM256 495000000 Hz -5.1 dBmV 39.9 dB 0 0
8 Locked QAM256 507000000 Hz -4.8 dBmV 40.0 dB 0 0
9 Locked QAM256 513000000 Hz -4.9 dBmV 39.9 dB 0 0
10 Locked QAM256 519000000 Hz -5.2 dBmV 40.0 dB 0 0
11 Locked QAM256 525000000 Hz -5.5 dBmV 40.0 dB 0 0
12 Locked QAM256 531000000 Hz -5.6 dBmV 39.8 dB 0 0
13 Locked QAM256 537000000 Hz -5.7 dBmV 39.6 dB 0 0
14 Locked QAM256 543000000 Hz -5.9 dBmV 39.7 dB 0 0
15 Locked QAM256 549000000 Hz -5.9 dBmV 39.5 dB 0 0
16 Locked QAM256 555000000 Hz -5.6 dBmV 39.6 dB 0 0
17 Locked QAM256 561000000 Hz -5.2 dBmV 39.7 dB 0 0
18 Locked QAM256 567000000 Hz -5.3 dBmV 39.8 dB 0 0
19 Locked QAM256 573000000 Hz -5.3 dBmV 39.7 dB 0 0
20 Locked QAM256 579000000 Hz -5.5 dBmV 39.5 dB 0 0
21 Locked QAM256 585000000 Hz -5.7 dBmV 39.3 dB 0 0
22 Locked QAM256 591000000 Hz -5.8 dBmV 39.4 dB 0 0
23 Locked QAM256 597000000 Hz -5.7 dBmV 39.5 dB 0 0
24 Locked QAM256 603000000 Hz -5.9 dBmV 39.4 dB 0 0
25 Locked QAM256 609000000 Hz -5.9 dBmV 39.4 dB 0 0
27 Locked QAM256 621000000 Hz -5.7 dBmV 39.3 dB 0 0
28 Locked QAM256 627000000 Hz -5.5 dBmV 39.3 dB 0 0
29 Locked QAM256 639000000 Hz -5.5 dBmV 39.3 dB 0 0
30 Locked QAM256 645000000 Hz -5.4 dBmV 39.4 dB 0 0
32 Locked QAM256 657000000 Hz -5.7 dBmV 39.4 dB 0 0
33 Locked Other 690000000 Hz -5.5 dBmV 37.8 dB 5995792 0
New Poster

Re: Modem constantly keeps resetting

Here is my current event log as well:

The table below contains the log of events that the SB8200 has detected. This log can be important to the service provider to help diagnose and correct problems, if any should occur.

Date Time Event ID Event Level Description
04/13/2019 15:20 67061600 6 "DS profile assignment change. DS Chan ID: 32; Previous Profile: ; New Profile: 1.;CM-MAC=2c:58:4f:fe:33:79;CMTS-MAC=00:01:5c:b2:1a:50;CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:00 2436694066 6 "Honoring MDD; IP provisioning mode = IPv6"
01/01/1970 00:00 84000100 3 "SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=2c:58:4f:fe:33:79;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:01 82000400 3 "Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=2c:58:4f:fe:33:79;CMTS-MAC=00:01:5c:b2:1a:50;CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:00 84000100 3 "SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=2c:58:4f:fe:33:79;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;"
04/13/2019 15:16 82000400 3 "Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=2c:58:4f:fe:33:79;CMTS-MAC=00:01:5c:b2:1a:50;CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:08 82000400 3 "Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=2c:58:4f:fe:33:79;CMTS-MAC=00:01:5c:b2:1a:50;CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:06 84000100 3 "SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=2c:58:4f:fe:33:79;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:06 82000400 3 "Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=2c:58:4f:fe:33:79;CMTS-MAC=00:01:5c:b2:1a:50;CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:02 84000100 3 "SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=2c:58:4f:fe:33:79;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:01 82000400 3 "Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=2c:58:4f:fe:33:79;CMTS-MAC=00:01:5c:b2:1a:50;CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:00 84000100 3 "SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=2c:58:4f:fe:33:79;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:04 82000400 3 "Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=2c:58:4f:fe:33:79;CMTS-MAC=00:01:5c:b2:1a:50;CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:02 84000100 3 "SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=2c:58:4f:fe:33:79;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:01 82000400 3 "Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=2c:58:4f:fe:33:79;CMTS-MAC=00:01:5c:b2:1a:50;CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:00 84000100 3 "SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=2c:58:4f:fe:33:79;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:12 82000400 3 "Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=2c:58:4f:fe:33:79;CMTS-MAC=00:01:5c:b2:1a:50;CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:06 84000100 3 "SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=2c:58:4f:fe:33:79;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:06 82000400 3 "Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=2c:58:4f:fe:33:79;CMTS-MAC=00:01:5c:b2:1a:50;CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:02 84000100 3 "SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=2c:58:4f:fe:33:79;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:01 82000400 3 "Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=2c:58:4f:fe:33:79;CMTS-MAC=00:01:5c:b2:1a:50;CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:00 84000100 3 "SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=2c:58:4f:fe:33:79;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;"
04/13/2019 14:32 82000400 3 "Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=2c:58:4f:fe:33:79;CMTS-MAC=00:01:5c:b2:1a:50;CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:00 84000100 3 "SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=2c:58:4f:fe:33:79;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:09 82000400 3 "Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=2c:58:4f:fe:33:79;CMTS-MAC=00:01:5c:b2:1a:50;CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:06 84000100 3 "SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=2c:58:4f:fe:33:79;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:06 82000400 3 "Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=2c:58:4f:fe:33:79;CMTS-MAC=00:01:5c:b2:1a:50;CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:02 84000100 3 "SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=2c:58:4f:fe:33:79;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:01 82000400 3 "Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=2c:58:4f:fe:33:79;CMTS-MAC=00:01:5c:b2:1a:50;CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:00 84000100 3 "SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=2c:58:4f:fe:33:79;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;"
04/13/2019 14:03 82000400 3 "Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=2c:58:4f:fe:33:79;CMTS-MAC=00:01:5c:b2:1a:50;CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:00 84000100 3 "SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=2c:58:4f:fe:33:79;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:09 82000400 3 "Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=2c:58:4f:fe:33:79;CMTS-MAC=00:01:5c:b2:1a:50;CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:08 82000500 3 "Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=2c:58:4f:fe:33:79;CMTS-MAC=00:01:5c:b2:1a:50;CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:08 82000200 3 "No Ranging Response received - T3 time-out;CM-MAC=2c:58:4f:fe:33:79;CMTS-MAC=00:01:5c:b2:1a:50;CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:03 82000400 3 "Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=2c:58:4f:fe:33:79;CMTS-MAC=00:01:5c:b2:1a:50;CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:02 82000500 3 "Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=2c:58:4f:fe:33:79;CMTS-MAC=00:01:5c:b2:1a:50;CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:02 84000100 3 "SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=2c:58:4f:fe:33:79;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:01 82000400 3 "Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=2c:58:4f:fe:33:79;CMTS-MAC=00:01:5c:b2:1a:50;CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:00 82000500 3 "Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=2c:58:4f:fe:33:79;CMTS-MAC=00:01:5c:b2:1a:50;CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:00 84000100 3 "SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=2c:58:4f:fe:33:79;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:14 82000400 3 "Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=2c:58:4f:fe:33:79;CMTS-MAC=00:01:5c:b2:1a:50;CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:06 84000100 3 "SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=2c:58:4f:fe:33:79;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:06 82000400 3 "Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=2c:58:4f:fe:33:79;CMTS-MAC=00:01:5c:b2:1a:50;CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:02 84000100 3 "SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=2c:58:4f:fe:33:79;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:01 82000400 3 "Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=2c:58:4f:fe:33:79;CMTS-MAC=00:01:5c:b2:1a:50;CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:00 84000100 3 "SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=2c:58:4f:fe:33:79;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;"
Expert

Re: Modem constantly keeps resetting

The upstream power is too high / out of spec, and the downstream power is on the weak side. That can cause random disconnects, spontaneous re-booting of the modem, and speed 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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I am a Customer Expert volunteering my time to help other customers here in the Forums.
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