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Internet dropping, random disconnects, T3 time outs.

New Poster

Internet dropping, random disconnects, T3 time outs.

I have contacted CS three times so far and they just reset my modem and the uncorrectables/correctables build back up and my internet drops connection randomly. I'm hardwired to a 1 gigabit ethernet port on both my CM1000 and XR500. Is there anything you can do to help me further at this point? Here's my Modem stats: 


Starting Frequency

Startup Procedure

Acquire Downstream Channel609000000 HzLocked
Connectivity StateOKOperational
Boot StateOKOperational
IP Provisioning ModeHonor MDDIPv6 only

Downstream Bonded Channels

ChannelLock StatusModulationChannel IDFrequencyPowerSNR / MERUnerrored CodewordsCorrectable CodewordsUncorrectable Codewords
1LockedQAM25636609000000 Hz2.1 dBmV42.8 dB808516961160
2LockedQAM2568435000000 Hz3.7 dBmV44.6 dB8074391605731
3LockedQAM2569441000000 Hz3.6 dBmV44.4 dB8074417793748
4LockedQAM25610447000000 Hz3.5 dBmV44.4 dB8074465573455
5LockedQAM25611453000000 Hz3.4 dBmV44.5 dB8074499167135
6LockedQAM25612459000000 Hz3.3 dBmV44.4 dB8074537065428
7LockedQAM25613465000000 Hz3.2 dBmV44.3 dB8074570833351
8LockedQAM25614471000000 Hz3.1 dBmV44.1 dB8074607293056
9LockedQAM25615477000000 Hz3.1 dBmV44.1 dB8074777883154
10LockedQAM25616483000000 Hz2.9 dBmV43.9 dB8074776506514
11LockedQAM25617489000000 Hz2.8 dBmV43.9 dB8074828784636
12LockedQAM25618495000000 Hz2.7 dBmV43.8 dB8074891024235
13LockedQAM25619507000000 Hz2.5 dBmV43.6 dB8074914965515
14LockedQAM25620513000000 Hz2.4 dBmV43.5 dB8074850024044
15LockedQAM25621519000000 Hz2.4 dBmV43.4 dB807501216670
16LockedQAM25622525000000 Hz2.3 dBmV43.3 dB807504420750
17LockedQAM25623531000000 Hz2.4 dBmV43.5 dB807530424550
18LockedQAM25624537000000 Hz2.3 dBmV43.5 dB807535260520
19LockedQAM25625543000000 Hz2.1 dBmV43.4 dB807533811600
20LockedQAM25626549000000 Hz2.1 dBmV43.4 dB807539290530
21LockedQAM25627555000000 Hz1.9 dBmV43.3 dB807545064440
22LockedQAM25628561000000 Hz2.0 dBmV43.3 dB807548341520
23LockedQAM25629567000000 Hz1.9 dBmV43.1 dB807552201370
24LockedQAM25630573000000 Hz1.9 dBmV43.0 dB807554016640
25LockedQAM25631579000000 Hz2.1 dBmV43.3 dB807560601300
26LockedQAM25632585000000 Hz2.0 dBmV43.1 dB807563776339
27LockedQAM25633591000000 Hz2.1 dBmV43.1 dB807566120470
28LockedQAM25634597000000 Hz2.3 dBmV43.1 dB807571244210
29LockedQAM25635603000000 Hz2.2 dBmV43.0 dB807576381310
30LockedQAM25637615000000 Hz1.9 dBmV42.7 dB807574845390
31LockedQAM25638621000000 Hz1.8 dBmV42.6 dB807577053290
32Not LockedUnknown00 Hz0.0 dBmV0.0 dB000

Upstream Bonded Channels

ChannelLock StatusModulationChannel IDFrequencyPower
1LockedATDMA919300000 Hz47.5 dBmV
2LockedATDMA1025700000 Hz47.5 dBmV
3LockedATDMA1132300000 Hz48.0 dBmV
4LockedATDMA1238700000 Hz48.3 dBmV
5Not LockedUnknown00 Hz0.0 dBmV
6Not LockedUnknown00 Hz0.0 dBmV
7Not LockedUnknown00 Hz0.0 dBmV
8Not LockedUnknown00 Hz0.0 dBmV

Downstream OFDM Channels

ChannelLock StatusModulation / Profile IDChannel IDFrequencyPowerSNR / MERActive Subcarrier Number RangeUnerrored CodewordsCorrectable CodewordsUncorrectable Codewords
1Locked0, 1, 2, 348688000000 Hz1.9 dBmV39.3 dB1108 ~ 29875512570327559538256
2Not Locked000 Hz2.8 dBmV0.0 dB0 ~ 4095000

Upstream OFDMA Channels

ChannelLock StatusModulation / Profile IDChannel IDFrequencyPower
1Not LockedUnknown00 Hz0 dBmV
2Not LockedUnknown00 Hz0 dBmV


New Poster

Re: Internet dropping, random disconnects, T3 time outs.

We are suddenly experiencing the same thing. Obviously it cannot be that just restarting/rebooting modems all the time is the solution. And from these threads, it's clearly a variety of modems experiencing this.

Re: Internet dropping, random disconnects, T3 time outs.

The upstream power is on the high side and it may be intermittently fluctuating even higher to out of spec levels. 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.

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New Poster

Re: Internet dropping, random disconnects, T3 time outs.

I replaced the sole splitter a month ago and it fixed the upstream from being above 50. However, everyone in the town seems to ride upper 40's and they won't do anything about it. Odd. 🙂