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Intermittent outages, and speeds consistently dropping around 90-100 mbps on a 200 mbps plan.

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Intermittent outages, and speeds consistently dropping around 90-100 mbps on a 200 mbps plan.

Hi, we have been having intermittent issues for sometime now. Randomly, about once or twice a week the internet will go down. It always seems to be early in the morning. We have also been having very sluggish internet. There are about 6 devices normally connected, but usually only about 3 are ever in use at once. Had an arris modem and just recently switched to a motorola mb7621. We also use a netgear nithawk ac1900. A few weeks back, a rep told us our signal was looking low and they would get it looked at. A guy come out and supposedly fixed it according to a rep I recently spoke with who told me the signals were looking good on his end. We have changed all connectivity cables, made sure they were to spec, cycled the modems and router. Can someone look at the down and up info and tell me if they see anything of concern? Thanks.

 

connection

   Channel Lock Status Modulation Channel ID Freq. (MHz) Pwr (dBmV) SNR (dB) Corrected Uncorrected
1 Locked QAM256 2 489.0 -9.1 40.7 0 0
2 Locked QAM256 1 483.0 -9.0 40.8 0 0
3 Locked QAM256 3 495.0 -9.2 40.6 0 0
4 Locked QAM256 4 501.0 -9.5 40.4 0 0
5 Locked QAM256 5 507.0 -9.4 37.1 0 0
6 Locked QAM256 6 513.0 -9.4 40.5 0 0
7 Locked QAM256 7 519.0 -9.0 40.7 0 0
8 Locked QAM256 8 525.0 -8.9 40.6 0 0
9 Locked QAM256 9 531.0 -8.4 41.0 0 0
10 Locked QAM256 10 537.0 -8.2 40.9 0 0
11 Locked QAM256 11 543.0 -7.9 41.1 0 0
12 Locked QAM256 12 549.0 -7.9 41.3 0 0
13 Locked QAM256 13 555.0 -8.4 40.8 0 0
14 Locked QAM256 14 561.0 -8.4 40.9 0 0
15 Locked QAM256 15 567.0 -8.9 40.5 0 0
16 Locked QAM256 16 573.0 -8.9 40.5 0 0
17 Locked QAM256 17 579.0 -9.5 41.3 0 0
18 Locked QAM256 18 585.0 -9.5 41.4 0 0
19 Locked QAM256 19 591.0 -9.7 41.0 0 0
20 Locked QAM256 20 597.0 -9.8 41.0 0 0
21 Locked QAM256 21 603.0 -9.3 41.3 0 0
22 Locked QAM256 22 609.0 -9.4 41.1 0 0
23 Locked QAM256 23 615.0 -9.4 41.3 0 0
24 Locked QAM256 24 621.0 -9.5 41.1 0 0
Total             0 0



   Upstream Bonded Channels
 

 

 
 

 


  
   Channel Lock Status Channel Type Channel ID Symb. Rate (Ksym/sec) Freq. (MHz) Pwr (dBmV)
1 Locked ATDMA 41 5120 35.8 46.8
2 Locked ATDMA 42 5120 29.4 46.5
3 Locked ATDMA 43 5120 23.0 46.0
4 Not Locked Unknown 0 0 0 0.0
5 Not Locked Unknown 0 0 0 0.0
6 Not Locked Unknown 0 0 0 0.0
7 Not Locked Unknown 0 0 0 0.0
8 Not Locked Unknown 0 0 0 0.0

 

 

 

Event Log

 Fri Apr 24 15:16:30 2020    Critical (3)   Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=00:40:36:65:85:5b;CMTS-MAC=00:01:5c:8f:1a:57;CM-QOS=1.1;CM-VER=3.0; 
 Fri Apr 24 15:16:57 2020    Critical (3)   SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=00:40:36:65:85:5b;CMTS-MAC=00:01:5c:8f:1a:57;CM-QOS=1.1;CM-VER=3.0; 
 Fri Apr 24 15:17:04 2020    Critical (3)   SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=00:40:36:65:85:5b;CMTS-MAC=00:01:5c:8f:1a:57;CM-QOS=1.1;CM-VER=3.0; 
 Fri Apr 24 15:19:55 2020    Critical (3)   SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=00:40:36:65:85:5b;CMTS-MAC=00:01:5c:8f:1a:57;CM-QOS=1.1;CM-VER=3.0; 
 Fri Apr 24 15:19:55 2020    Critical (3)   Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=00:40:36:65:85:5b;CMTS-MAC=00:01:5c:8f:1a:57;CM-QOS=1.1;CM-VER=3.0; 
 Fri Apr 24 15:20:50 2020    Critical (3)   SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=00:40:36:65:85:5b;CMTS-MAC=00:01:5c:8f:1a:57;CM-QOS=1.1;CM-VER=3.0; 
 Fri Apr 24 15:20:51 2020    Critical (3)   Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=00:40:36:65:85:5b;CMTS-MAC=00:01:5c:8f:1a:57;CM-QOS=1.1;CM-VER=3.0; 
 Fri Apr 24 15:21:08 2020    Critical (3)   SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=00:40:36:65:85:5b;CMTS-MAC=00:01:5c:8f:1a:57;CM-QOS=1.1;CM-VER=3.0; 
 Fri Apr 24 15:21:08 2020    Critical (3)   Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=00:40:36:65:85:5b;CMTS-MAC=00:01:5c:8f:1a:57;CM-QOS=1.1;CM-VER=3.0; 
 Fri Apr 24 15:21:10 2020    Critical (3)   SYNC Timing Synchronization failure - Failed to acquire FEC framing;CM-MAC=00:40:36:65:85:5b;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0; 
 Fri Apr 24 15:23:57 2020    Critical (3)   SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=00:40:36:65:85:5b;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0; 
 Tue Apr 28 15:53:18 2020    Critical (3)   Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=00:40:36:65:85:5b;CMTS-MAC=00:01:5c:8f:1a:57;CM-QOS=1.1;CM-VER=3.0; 
 Fri May 01 05:54:17 2020    Critical (3)   SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=00:40:36:65:85:5b;CMTS-MAC=00:01:5c:8f:1a:57;CM-QOS=1.1;CM-VER=3.0; 
 Fri May 01 05:54:24 2020    Critical (3)   SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=00:40:36:65:85:5b;CMTS-MAC=00:01:5c:8f:1a:57;CM-QOS=1.1;CM-VER=3.0; 
 Fri May 01 05:57:48 2020    Critical (3)   SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=00:40:36:65:85:5b;CMTS-MAC=00:01:5c:8f:1a:57;CM-QOS=1.1;CM-VER=3.0; 
 Fri May 01 05:57:48 2020    Critical (3)   Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=00:40:36:65:85:5b;CMTS-MAC=00:01:5c:8f:1a:57;CM-QOS=1.1;CM-VER=3.0; 
 Fri May 01 05:57:54 2020    Critical (3)   SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=00:40:36:65:85:5b;CMTS-MAC=00:01:5c:8f:1a:57;CM-QOS=1.1;CM-VER=3.0; 
 Fri May 01 05:57:55 2020    Critical (3)   Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=00:40:36:65:85:5b;CMTS-MAC=00:01:5c:8f:1a:57;CM-QOS=1.1;CM-VER=3.0; 
 Fri May 01 05:58:08 2020    Critical (3)   SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=00:40:36:65:85:5b;CMTS-MAC=00:01:5c:8f:1a:57;CM-QOS=1.1;CM-VER=3.0; 
 Fri May 01 05:58:08 2020    Critical (3)   Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=00:40:36:65:85:5b;CMTS-MAC=00:01:5c:8f:1a:57;CM-QOS=1.1;CM-VER=3.0; 
 Fri May 01 05:58:10 2020    Critical (3)   SYNC Timing Synchronization failure - Failed to acquire FEC framing;CM-MAC=00:40:36:65:85:5b;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0; 
 Fri May 01 06:00:57 2020    Critical (3)   SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=00:40:36:65:85:5b;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0; 
 Thu May 14 14:46:33 2020    Critical (3)   Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=00:40:36:65:85:5b;CMTS-MAC=00:01:5c:8f:1a:57;CM-QOS=1.1;CM-VER=3.0; 
 Thu May 14 14:57:51 2020    Critical (3)   Resetting the cable modem due to docsDevResetNow 
 Time Not Established   Critical (3)   No Ranging Response received - T3 time-out;CM-MAC=00:40:36:65:85:5b;CMTS-MAC=00:01:5c:8f:1a:57;CM-QOS=1.0;CM-VER=3.0; 
 Time Not Established   Critical (3)   SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=00:40:36:65:85:5b;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0; 
 Time Not Established   Critical (3)   No Ranging Response received - T3 time-out;CM-MAC=00:40:36:65:85:5b;CMTS-MAC=00:01:5c:8f:1a:57;CM-QOS=1.0;CM-VER=3.0; 
 Time Not Established   Notice (6) 

 Honoring MDD; IP provisioning mode = IPv6

 

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Expert

Re: Intermittent outages, and speeds consistently dropping around 90-100 mbps on a 200 mbps plan.

The downstream power is on the weak / low side and it may be intermittently fluctuating even lower 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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