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Intermittent Slow Connection

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Intermittent Slow Connection



Over the past month or so, I've had intermittent connection issues. I pay for 600Mbps service, but on occassion I see my speeds drop to a consistent 60/90Mbps. Sometimes this will correct over night or during the day. Since I live in a small apartment building, I don't really have access to the cable lines outside of my room, but I can confirm there are no splitters inside my apartment.


When I talked to customer service, I was told they didn't see anything wrong on their end, but that they would continue investigation in the background and maybe send a tech. I never got a case number to follow up with, and no one has contacted me about this and it's been a couple weeks. I figured one of you helpful few could confirm that my numbers are slightly out of spec. (My speeds are satisfactory right now, but when they aren't, my Uncorrectables are in the millions.)


Startup Procedure
Procedure Status Comment
Acquire Downstream Channel561000000 HzLocked
Connectivity StateOKOperational
Boot StateOKOperational
IP Provisioning ModeHonor MDDIPv6 only
Downstream Bonded Channels
ChannelLock StatusModulationChannel IDFrequencyPowerSNRCorrectablesUncorrectables
1LockedQAM25632561000000 Hz-10.1 dBmV33.9 dB271440839
2LockedQAM25612435000000 Hz-9.3 dBmV38.8 dB54316412
3LockedQAM25613441000000 Hz-9.4 dBmV38.7 dB31083139
4LockedQAM25614447000000 Hz-9.4 dBmV38.8 dB28801194
5LockedQAM25615453000000 Hz-9.4 dBmV35.8 dB581294571
6LockedQAM25616459000000 Hz-9.6 dBmV38.1 dB9459125705
7LockedQAM25617465000000 Hz-9.6 dBmV36.8 dB9650020657
8LockedQAM25618471000000 Hz-9.7 dBmV37.9 dB78702174
9LockedQAM25619477000000 Hz-9.9 dBmV37.8 dB133946185
10LockedQAM25620483000000 Hz-10.1 dBmV37.4 dB187857153
11LockedQAM25621489000000 Hz-10.4 dBmV38.6 dB2441131028
12LockedQAM25622495000000 Hz-10.3 dBmV39.1 dB256817145
13Not LockedUnknown00 Hz0.0 dBmV0.0 dB00
14Not LockedUnknown00 Hz0.0 dBmV0.0 dB00
15LockedQAM25625519000000 Hz-10.1 dBmV33.7 dB167400207
16LockedQAM25626525000000 Hz-9.9 dBmV32.2 dB310395226
17LockedQAM25627531000000 Hz-9.9 dBmV35.7 dB60
18LockedQAM25628537000000 Hz-9.9 dBmV39.5 dB230
19LockedQAM25629543000000 Hz-10.1 dBmV38.5 dB20
20LockedQAM25630549000000 Hz-10.1 dBmV37.3 dB50
21LockedQAM25631555000000 Hz-10.2 dBmV30.7 dB00
22LockedQAM25633567000000 Hz-10.6 dBmV34.0 dB00
23LockedQAM25634573000000 Hz-10.4 dBmV34.6 dB00
24LockedQAM25635579000000 Hz-10.6 dBmV34.3 dB330
Upstream Bonded Channels
ChannelLock StatusUS Channel TypeChannel IDSymbol RateFrequencyPower
1LockedATDMA75120 Ksym/sec30300000 Hz50.5 dBmV
2LockedATDMA85120 Ksym/sec36700000 Hz50.8 dBmV
3LockedATDMA65120 Ksym/sec23700000 Hz49.5 dBmV
4LockedATDMA55120 Ksym/sec17300000 Hz48.3 dBmV
5Not LockedUnknown00 Ksym/sec0 Hz0.0 dBmV
6Not LockedUnknown00 Ksym/sec0 Hz0.0 dBmV
7Not LockedUnknown00 Ksym/sec0 Hz0.0 dBmV
8Not LockedUnknown00 Ksym/sec0 Hz0.0 dBmV
Current System Time: Mon Aug 03 08:03:02 2020
System Up Time: 10:22:30

Re: Intermittent Slow Connection

There is a problem with the downstream and the upstream power. 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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