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Constant T3 Timeouts, internet drops, slow speeds

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Constant T3 Timeouts, internet drops, slow speeds

Huge issues w/ internet dropouts. Error log and power levels shown below. Hesitant to have a tech out after the one who came yesterday was very little help, didn't wear a mask, and dropped trash all over my driveway. Any ideas? I have gigabit, but as of this morning I can't get more than 30Mbps down after usually sitting more around 400-500Mbps (wifi)

 

<tabindex=-1>Downstream Bonded Channels (Partial Service)</tabindex=-1>
ChannelLock StatusModulationChannel IDFrequencyPowerSNRCorrectablesUncorrectabables
1LockedQAM25629597000000 Hz7.4 dBmV42.4 dB93445377
2LockedQAM2561411000000 Hz8.4 dBmV43.5 dB4147935959
3LockedQAM2562417000000 Hz8.5 dBmV43.3 dB4066940470
4LockedQAM2563435000000 Hz7.1 dBmV42.7 dB4401940457
5LockedQAM2564441000000 Hz8.2 dBmV43.5 dB4431440424
6LockedQAM2565453000000 Hz6.9 dBmV43.0 dB4199240769
7LockedQAM2566459000000 Hz7.3 dBmV43.0 dB4256738884
8LockedQAM2567465000000 Hz7.3 dBmV42.5 dB4449242670
9LockedQAM2568471000000 Hz6.6 dBmV42.8 dB4762645947
10LockedQAM2569477000000 Hz6.3 dBmV42.6 dB5166847196
11LockedQAM25610483000000 Hz7.4 dBmV43.1 dB4528244058
12LockedQAM25611489000000 Hz8.0 dBmV43.4 dB4641143890
13LockedQAM25612495000000 Hz7.3 dBmV42.7 dB5077449500
14LockedQAM25613501000000 Hz6.9 dBmV42.6 dB5325647933
15LockedQAM25614507000000 Hz7.0 dBmV42.6 dB5469848685
16LockedQAM25615513000000 Hz7.1 dBmV42.8 dB6183159454
17LockedQAM25616519000000 Hz7.1 dBmV42.7 dB5706044322
18LockedQAM25617525000000 Hz6.8 dBmV42.4 dB5221346576
19LockedQAM25618531000000 Hz6.8 dBmV42.5 dB6690863551
20LockedQAM25619537000000 Hz6.9 dBmV42.3 dB6636864461
21LockedQAM25620543000000 Hz7.0 dBmV42.3 dB6931263363
22LockedQAM25621549000000 Hz7.1 dBmV42.3 dB7115869995
23LockedQAM25622555000000 Hz7.0 dBmV42.4 dB7623878242
24LockedQAM25623561000000 Hz7.0 dBmV42.1 dB8121184003
25LockedQAM25624567000000 Hz7.1 dBmV42.4 dB8020684294
26LockedQAM25625573000000 Hz7.1 dBmV42.4 dB8456592857
27LockedQAM25626579000000 Hz6.6 dBmV42.2 dB90102103691
28LockedQAM25627585000000 Hz5.9 dBmV41.7 dB92354109860
29LockedQAM25628591000000 Hz7.4 dBmV42.5 dB90025104781
30LockedQAM25630603000000 Hz7.3 dBmV42.3 dB97001118323
31LockedQAM25631609000000 Hz7.2 dBmV42.3 dB94184114953
32LockedQAM25632615000000 Hz7.0 dBmV41.8 dB109207143632

<tabindex=-1>Upstream Bonded Channels</tabindex=-1>
ChannelLock StatusUS Channel TypeChannel IDSymbol RateFrequencyPower
1LockedATDMA105120 Ksym/sec22800000 Hz51.3 dBmV
2LockedATDMA95120 Ksym/sec16400000 Hz54.3 dBmV
3LockedATDMA115120 Ksym/sec29200000 Hz49.8 dBmV
4LockedATDMA125120 Ksym/sec35600000 Hz48.8 dBmV
5LockedATDMA131280 Ksym/sec40400000 Hz45.8 dBmV
6Not LockedUnknown00 Ksym/sec0 Hz0 dBmV
7Not LockedUnknown00 Ksym/sec0 Hz0 dBmV
8Not LockedUnknown00 Ksym/sec0 Hz

0 dBmV

 

 

TimePriorityDescription
2020-10-01, 10:56:50Critical (3)Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=08:36:c9:cc:59:58;CMTS-MAC=24:7e:12:f0:d3:22;CM-QOS=1.1;CM-VER=3.1;
2020-10-01, 08:20:51Warning (5)MDD message timeout;CM-MAC=08:36:c9:cc:59:58;CMTS-MAC=24:7e:12:f0:d3:22;CM-QOS=1.1;CM-VER=3.1;
2020-10-01, 07:45:28Critical (3)Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=08:36:c9:cc:59:58;CMTS-MAC=24:7e:12:f0:d3:22;CM-QOS=1.1;CM-VER=3.1;
2020-09-30, 19:48:07Warning (5)MDD message timeout;CM-MAC=08:36:c9:cc:59:58;CMTS-MAC=24:7e:12:f0:d3:22;CM-QOS=1.1;CM-VER=3.1;
2020-09-30, 12:27:00Critical (3)Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=08:36:c9:cc:59:58;CMTS-MAC=24:7e:12:f0:d3:22;CM-QOS=1.1;CM-VER=3.1;
2020-09-30, 11:11:35Warning (5)MDD message timeout;CM-MAC=08:36:c9:cc:59:58;CMTS-MAC=24:7e:12:f0:d3:22;CM-QOS=1.1;CM-VER=3.1;
2020-09-30, 11:08:07Critical (3)16 consecutive T3 timeouts while trying to range on upstream channel 0;CM-MAC=08:36:c9:cc:59:58;CMTS-MAC=24:7e:12:f0:d3:22;CM-QOS=1.1;CM-VER=3.1;
2020-09-30, 11:08:07Critical (3)Unicast Maintenance Ranging attempted - No response - Retries exhausted;CM-MAC=08:36:c9:cc:59:58;CMTS-MAC=24:7e:12:f0:d3:22;CM-QOS=1.1;CM-VER=3.1;
2020-09-30, 11:07:07Critical (3)Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=08:36:c9:cc:59:58;CMTS-MAC=24:7e:12:f0:d3:22;CM-QOS=1.1;CM-VER=3.1;
2020-09-30, 11:06:35Warning (5)MDD message timeout;CM-MAC=08:36:c9:cc:59:58;CMTS-MAC=24:7e:12:f0:d3:22;CM-QOS=1.1;CM-VER=3.1;
2020-09-30, 11:06:07Critical (3)Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=08:36:c9:cc:59:58;CMTS-MAC=24:7e:12:f0:d3:22;CM-QOS=1.1;CM-VER=3.1;
2020-09-30, 11:04:59Warning (5)MDD message timeout;CM-MAC=08:36:c9:cc:59:58;CMTS-MAC=24:7e:12:f0:d3:22;CM-QOS=1.1;CM-VER=3.1;
2020-09-30, 11:04:48Critical (3)SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=08:36:c9:cc:59:58;CMTS-MAC=24:7e:12:f0:d3:22;CM-QOS=1.1;CM-VER=3.1;
2020-09-30, 10:50:15Warning (5)MDD message timeout;CM-MAC=08:36:c9:cc:59:58;CMTS-MAC=24:7e:12:f0:d3:22;CM-QOS=1.1;CM-VER=3.1;
2020-09-30, 10:50:10Critical (3)Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=08:36:c9:cc:59:58;CMTS-MAC=24:7e:12:f0:d3:22;CM-QOS=1.1;CM-VER=3.1;
2020-09-30, 10:48:55Warning (5)MDD message timeout;CM-MAC=08:36:c9:cc:59:58;CMTS-MAC=24:7e:12:f0:d3:22;CM-QOS=1.1;CM-VER=3.1;
2020-09-30, 10:48:29Critical (3)Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=08:36:c9:cc:59:58;CMTS-MAC=24:7e:12:f0:d3:22;CM-QOS=1.1;CM-VER=3.1;
2020-09-30, 10:48:09Warning (5)MDD message timeout;CM-MAC=08:36:c9:cc:59:58;CMTS-MAC=24:7e:12:f0:d3:22;CM-QOS=1.1;CM-VER=3.1;
2020-09-30, 10:48:09Critical (3)Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=08:36:c9:cc:59:58;CMTS-MAC=24:7e:12:f0:d3:22;CM-QOS=1.1;CM-VER=3.1;
2020-09-30, 10:47:51Warning (5)MDD message timeout;CM-MAC=08:36:c9:cc:59:58;CMTS-MAC=24:7e:12:f0:d3:22;CM-QOS=1.1;CM-VER=3.1;
2020-09-30, 10:47:49Critical (3)Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=08:36:c9:cc:59:58;CMTS-MAC=24:7e:12:f0:d3:22;CM-QOS=1.1;CM-VER=3.1;
2020-09-30, 10:47:35Warning (5)MDD message timeout;CM-MAC=08:36:c9:cc:59:58;CMTS-MAC=24:7e:12:f0:d3:22;CM-QOS=1.1;CM-VER=3.1;
2020-09-30, 10:47:29Critical (3)Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=08:36:c9:cc:59:58;CMTS-MAC=24:7e:12:f0:d3:22;CM-QOS=1.1;CM-VER=3.1;
2020-09-30, 10:47:11Warning (5)MDD message timeout;CM-MAC=08:36:c9:cc:59:58;CMTS-MAC=24:7e:12:f0:d3:22;CM-QOS=1.1;CM-VER=3.1;
2020-09-30, 10:47:11Critical (3)Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=08:36:c9:cc:59:58;CMTS-MAC=24:7e:12:f0:d3:22;CM-QOS=1.1;CM-VER=3.1;
2020-09-30, 10:47:09Warning (5)MDD message timeout;CM-MAC=08:36:c9:cc:59:58;CMTS-MAC=24:7e:12:f0:d3:22;CM-QOS=1.1;CM-VER=3.1;
2020-09-30, 10:35:11Critical (3)Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=08:36:c9:cc:59:58;CMTS-MAC=24:7e:12:f0:d3:22;CM-QOS=1.1;CM-VER=3.1;
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Contributor

Re: Constant T3 Timeouts, internet drops, slow speeds

Keep calling Comcast every day and requesting an onsite tech to test and record the issues. Until they escalate the issue to the appropriate team (maintenance team) if its not related to your internal network. Also make sure to ask for a credit daily for the interruptions, only way to lay a fire under Comcast butt is when they lose money daily/weekly/monthly on an existing issue.

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Expert

Re: Constant T3 Timeouts, internet drops, slow speeds

@sneakyewok 

 

The upstream power is on the high side and it may be intermittently fluctuating even higher to out of spec levels. The downstream power is on the high side as well/That can cause random disconnects, spontaneous re-booting of the modem, speed, packet loss, latency problems, and the un-bonding of channels.

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, and properly balance your line.



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