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Unstable Signal after switching to Gigabit service

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Unstable Signal after switching to Gigabit service

I upgraded to gigabit service mid September, and since then I've had nothing but connection issues. I've been through multiple modems including 2 different versions of the Netgear CM1000v2 and an Arris SB8200 (current modem), and two different routers (a TP-Link and a Netgear, both rated for gigabit speeds).

 

I've called over 20 times to try and troubleshoot the issue and frankly I'm tired of being told to reset my modem, especially since it's already doing that on its own. I've had a tech come out who replaced some old cabling leading up to the house, but said they didn't see any other issue and couldn't do anything else about it. 

 

My internet will go out 2-10 times a day, sometimes with the modem staying connected, other times with the modem losing connection entirely and resetting. I know it's not a modem issue because the exact same problem happened across all 4 modems I've tried (3 of which are brand new). I know it's not a router issue as well because I test with a hardline from the modem to my desktop.

 

I've included a snapshot of my modem event log on one of the recent disconnects, and what the modem stats look like around that time.

 

Also I've been running ping plotter for the past few weeks just to make sure, and I've included a graph of the past two day's worth of packet loss data: https://imgur.com/uF8LCZ0 

 

Acquire Downstream Channel501000000 HzLocked
Connectivity StateOKOperational
Boot StateOKOperational
Configuration FileOK 
SecurityEnabledBPI+
DOCSIS Network Access EnabledAllowed 

 

 
Downstream Bonded Channels
Channel IDLock StatusModulationFrequencyPowerSNR/MERCorrectedUncorrectables
17LockedQAM256501000000 Hz7.5 dBmV38.8 dB326868
1LockedQAM256399000000 Hz8.0 dBmV40.4 dB1090
2LockedQAM256405000000 Hz8.4 dBmV40.4 dB1271
3LockedQAM256411000000 Hz8.9 dBmV40.7 dB11612
4LockedQAM256417000000 Hz9.5 dBmV41.0 dB1354
5LockedQAM256423000000 Hz10.3 dBmV41.3 dB12214
6LockedQAM256429000000 Hz10.9 dBmV41.5 dB1569
7LockedQAM256435000000 Hz11.2 dBmV41.5 dB2008
8LockedQAM256441000000 Hz10.7 dBmV40.8 dB78032
9LockedQAM256453000000 Hz8.5 dBmV39.5 dB99232
10LockedQAM256459000000 Hz7.2 dBmV38.8 dB107240
11LockedQAM256465000000 Hz6.1 dBmV38.0 dB136541
12LockedQAM256471000000 Hz5.3 dBmV37.7 dB145844
13LockedQAM256477000000 Hz5.1 dBmV37.3 dB155250
14LockedQAM256483000000 Hz5.1 dBmV37.3 dB191843
15LockedQAM256489000000 Hz5.5 dBmV37.6 dB199652
16LockedQAM256495000000 Hz6.4 dBmV37.7 dB229576
18LockedQAM256507000000 Hz9.0 dBmV37.7 dB4845122
19LockedQAM256513000000 Hz11.0 dBmV37.9 dB7195136
20LockedQAM256519000000 Hz13.1 dBmV39.4 dB235885
21LockedQAM256525000000 Hz14.2 dBmV40.4 dB102535
22LockedQAM256531000000 Hz12.9 dBmV38.6 dB1521140
23LockedQAM256537000000 Hz10.2 dBmV37.0 dB277165
24LockedQAM256543000000 Hz7.5 dBmV36.2 dB497960
25LockedQAM256555000000 Hz3.5 dBmV34.2 dB16693137
26LockedQAM256561000000 Hz2.4 dBmV33.4 dB29889205
27LockedQAM256567000000 Hz2.0 dBmV32.9 dB45808319
28LockedQAM256573000000 Hz2.1 dBmV32.6 dB55116408
29LockedQAM256579000000 Hz3.1 dBmV32.7 dB53787404
30LockedQAM256585000000 Hz5.6 dBmV33.3 dB44267339
31LockedQAM256591000000 Hz11.5 dBmV32.8 dB111342915997
45LockedOther690000000 Hz12.7 dBmV35.8 dB2590930
 
Upstream Bonded Channels
ChannelChannel IDLock StatusUS Channel TypeFrequencyWidthPower
12LockedSC-QAM Upstream29200000 Hz6400000 Hz35.0 dBmV
24LockedSC-QAM Upstream16400000 Hz6400000 Hz35.0 dBmV
35LockedSC-QAM Upstream39600000 Hz1600000 Hz36.0 dBmV
41LockedSC-QAM Upstream35600000 Hz6400000 Hz35.0 dBmV
53LockedSC-QAM Upstream22800000 Hz6400000 Hz35.0 dBmV

 

 

Date TimeEvent IDEvent LevelDescription
10/17/2020 13:26740101006"CM-STATUS message sent. Event Type Code: 1; Chan ID: 45; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=a8:97:cd:e7:07:d5;CMTS-MAC=00:01:5c:ab:76:96;CM-QOS=1.1;CM-VER=3.1;"
10/17/2020 13:26840203005"MDD message timeout;CM-MAC=a8:97:cd:e7:07:d5;CMTS-MAC=00:01:5c:ab:76:96;CM-QOS=1.1;CM-VER=3.1;"
10/17/2020 13:25740101006"CM-STATUS message sent. Event Type Code: 21; Chan ID: 32; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=a8:97:cd:e7:07:d5;CMTS-MAC=00:01:5c:ab:76:96;CM-QOS=1.1;CM-VER=3.1;"
10/17/2020 13:25670616006"DS profile assignment change. DS Chan ID: 32; Previous Profile: ; New Profile: 1 2 3.;CM-MAC=a8:97:cd:e7:07:d5;CMTS-MAC=00:01:5c:ab:76:96;CM-QOS=1.1;CM-VER=3.1;"
10/17/2020 13:2524366940666"Honoring MDD; IP provisioning mode = IPv6"
10/17/2020 13:25820002003"No Ranging Response received - T3 time-out;CM-MAC=a8:97:cd:e7:07:d5;CMTS-MAC=00:01:5c:ab:76:96;CM-QOS=1.1;CM-VER=3.1;"
10/17/2020 13:24840005003"SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=a8:97:cd:e7:07:d5;CMTS-MAC=00:01:5c:ab:76:96;CM-QOS=1.1;CM-VER=3.1;"
10/17/2020 13:24840001003"SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=a8:97:cd:e7:07:d5;CMTS-MAC=00:01:5c:ab:76:96;CM-QOS=1.1;CM-VER=3.1;"
10/17/2020 13:20740101006"CM-STATUS message sent. Event Type Code: 5; Chan ID: 1 20 22 24 25 26 27 28 29 30 31; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=a8:97:cd:e7:07:d5;CMTS-MAC=00:01:5c:ab:76:96;CM-QOS=1.1;CM-VER=3.1;"
10/17/2020 12:43740101006"CM-STATUS message sent. Event Type Code: 8; Chan ID: 1 2 3 4 5; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=a8:97:cd:e7:07:d5;CMTS-MAC=00:01:5c:ab:76:96;CM-QOS=1.1;CM-VER=3.1;"
10/17/2020 12:43820008003"16 consecutive T3 timeouts while trying to range on upstream channel 4;CM-MAC=a8:97:cd:e7:07:d5;CMTS-MAC=00:01:5c:ab:76:96;CM-QOS=1.1;CM-VER=3.1;"
10/17/2020 12:43820006003"Unicast Maintenance Ranging attempted - No response - Retries exhausted;CM-MAC=a8:97:cd:e7:07:d5;CMTS-MAC=00:01:5c:ab:76:96;CM-QOS=1.1;CM-VER=3.1;"
10/17/2020 12:43820005003"Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=a8:97:cd:e7:07:d5;CMTS-MAC=00:01:5c:ab:76:96;CM-QOS=1.1;CM-VER=3.1;"
10/17/2020 12:43820008003"16 consecutive T3 timeouts while trying to range on upstream channel 0;CM-MAC=a8:97:cd:e7:07:d5;CMTS-MAC=00:01:5c:ab:76:96;CM-QOS=1.1;CM-VER=3.1;"
10/17/2020 12:43820006003"Unicast Maintenance Ranging attempted - No response - Retries exhausted;CM-MAC=a8:97:cd:e7:07:d5;CMTS-MAC=00:01:5c:ab:76:96;CM-QOS=1.1;CM-VER=3.1;"
10/17/2020 12:43820005003"Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=a8:97:cd:e7:07:d5;CMTS-MAC=00:01:5c:ab:76:96;CM-QOS=1.1;CM-VER=3.1;"
10/17/2020 12:43740101006"CM-STATUS message sent. Event Type Code: 8; Chan ID: 1 4 5; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=a8:97:cd:e7:07:d5;CMTS-MAC=00:01:5c:ab:76:96;CM-QOS=1.1;CM-VER=3.1;"
10/17/2020 12:42820005003"Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=a8:97:cd:e7:07:d5;CMTS-MAC=00:01:5c:ab:76:96;CM-QOS=1.1;CM-VER=3.1;"
10/17/2020 12:42820008003"16 consecutive T3 timeouts while trying to range on upstream channel 1;CM-MAC=a8:97:cd:e7:07:d5;CMTS-MAC=00:01:5c:ab:76:96;CM-QOS=1.1;CM-VER=3.1;"
10/17/2020 12:42820006003"Unicast Maintenance Ranging attempted - No response - Retries exhausted;CM-MAC=a8:97:cd:e7:07:d5;CMTS-MAC=00:01:5c:ab:76:96;CM-QOS=1.1;CM-VER=3.1;"
10/17/2020 12:42820005003"Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=a8:97:cd:e7:07:d5;CMTS-MAC=00:01:5c:ab:76:96;CM-QOS=1.1;CM-VER=3.1;"
10/17/2020 12:42740101006"CM-STATUS message sent. Event Type Code: 4; Chan ID: 26 27 28 29 30 31; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=a8:97:cd:e7:07:d5;CMTS-MAC=00:01:5c:ab:76:96;CM-QOS=1.1;CM-VER=3.1;"
10/17/2020 12:42820005003"Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=a8:97:cd:e7:07:d5;CMTS-MAC=00:01:5c:ab:76:96;CM-QOS=1.1;CM-VER=3.1;"
10/17/2020 12:42740101006"CM-STATUS message sent. Event Type Code: 1; Chan ID: 45; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=a8:97:cd:e7:07:d5;CMTS-MAC=00:01:5c:ab:76:96;CM-QOS=1.1;CM-VER=3.1;"
10/17/2020 12:42820005003"Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=a8:97:cd:e7:07:d5;CMTS-MAC=00:01:5c:ab:76:96;CM-QOS=1.1;CM-VER=3.1;"
10/17/2020 12:42740101006"CM-STATUS message sent. Event Type Code: 8; Chan ID: 1 5; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=a8:97:cd:e7:07:d5;CMTS-MAC=00:01:5c:ab:76:96;CM-QOS=1.1;CM-VER=3.1;"
10/17/2020 12:42820005003"Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=a8:97:cd:e7:07:d5;CMTS-MAC=00:01:5c:ab:76:96;CM-QOS=1.1;CM-VER=3.1;"
10/17/2020 12:42740101006"CM-STATUS message sent. Event Type Code: 4; Chan ID: 26 27 28 29 30 31; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=a8:97:cd:e7:07:d5;CMTS-MAC=00:01:5c:ab:76:96;CM-QOS=1.1;CM-VER=3.1;"
10/17/2020 12:42820005003"Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=a8:97:cd:e7:07:d5;CMTS-MAC=00:01:5c:ab:76:96;CM-QOS=1.1;CM-VER=3.1;"
10/17/2020 12:42820008003"16 consecutive T3 timeouts while trying to range on upstream channel 2;CM-MAC=a8:97:cd:e7:07:d5;CMTS-MAC=00:01:5c:ab:76:96;CM-QOS=1.1;CM-VER=3.1;"
10/17/2020 12:42820006003"Unicast Maintenance Ranging attempted - No response - Retries exhausted;CM-MAC=a8:97:cd:e7:07:d5;CMTS-MAC=00:01:5c:ab:76:96;CM-QOS=1.1;CM-VER=3.1;"
10/17/2020 12:42820005003"Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=a8:97:cd:e7:07:d5;CMTS-MAC=00:01:5c:ab:76:96;CM-QOS=1.1;CM-VER=3.1;"
10/17/2020 12:42740101006"CM-STATUS message sent. Event Type Code: 1; Chan ID: 45; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=a8:97:cd:e7:07:d5;CMTS-MAC=00:01:5c:ab:76:96;CM-QOS=1.1;CM-VER=3.1;"
10/17/2020 12:41820005003"Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=a8:97:cd:e7:07:d5;CMTS-MAC=00:01:5c:ab:76:96;CM-QOS=1.1;CM-VER=3.1;"
10/17/2020 12:41740101006"CM-STATUS message sent. Event Type Code: 8; Chan ID: 1; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=a8:97:cd:e7:07:d5;CMTS-MAC=00:01:5c:ab:76:96;CM-QOS=1.1;CM-VER=3.1;"
10/17/2020 12:41820005003"Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=a8:97:cd:e7:07:d5;CMTS-MAC=00:01:5c:ab:76:96;CM-QOS=1.1;CM-VER=3.1;"
10/17/2020 12:41740101006"CM-STATUS message sent. Event Type Code: 4; Chan ID: 26 27 28 29 30 31; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=a8:97:cd:e7:07:d5;CMTS-MAC=00:01:5c:ab:76:96;CM-QOS=1.1;CM-VER=3.1;"
10/17/2020 12:41820005003"Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=a8:97:cd:e7:07:d5;CMTS-MAC=00:01:5c:ab:76:96;CM-QOS=1.1;CM-VER=3.1;"
10/17/2020 12:41820008003"16 consecutive T3 timeouts while trying to range on upstream channel 3;CM-MAC=a8:97:cd:e7:07:d5;CMTS-MAC=00:01:5c:ab:76:96;CM-QOS=1.1;CM-VER=3.1;"
10/17/2020 12:41820006003"Unicast Maintenance Ranging attempted - No response - Retries exhausted;CM-MAC=a8:97:cd:e7:07:d5;CMTS-MAC=00:01:5c:ab:76:96;CM-QOS=1.1;CM-VER=3.1;"
10/17/2020 12:41820005003"Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=a8:97:cd:e7:07:d5;CMTS-MAC=00:01:5c:ab:76:96;CM-QOS=1.1;CM-VER=3.1;"
10/17/2020 12:41740101006"CM-STATUS message sent. Event Type Code: 1; Chan ID: 45; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=a8:97:cd:e7:07:d5;CMTS-MAC=00:01:5c:ab:76:96;CM-QOS=1.1;CM-VER=3.1;"
10/17/2020 12:41820005003"Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=a8:97:cd:e7:07:d5;CMTS-MAC=00:01:5c:ab:76:96;CM-QOS=1.1;CM-VER=3.1;"
10/17/2020 12:41740101006"CM-STATUS message sent. Event Type Code: 4; Chan ID: 26 27 28 29 30 31; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=a8:97:cd:e7:07:d5;CMTS-MAC=00:01:5c:ab:76:96;CM-QOS=1.1;CM-VER=3.1;"
10/17/2020 12:41820005003"Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=a8:97:cd:e7:07:d5;CMTS-MAC=00:01:5c:ab:76:96;CM-QOS=1.1;CM-VER=3.1;"
10/17/2020 12:40740101006"CM-STATUS message sent. Event Type Code: 1; Chan ID: 45; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=a8:97:cd:e7:07:d5;CMTS-MAC=00:01:5c:ab:76:96;CM-QOS=1.1;CM-VER=3.1;"
10/17/2020 12:40820005003"Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=a8:97:cd:e7:07:d5;CMTS-MAC=00:01:5c:ab:76:96;CM-QOS=1.1;CM-VER=3.1;"
10/17/2020 12:40740101006"CM-STATUS message sent. Event Type Code: 4; Chan ID: 26 27 28 29 30 31; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=a8:97:cd:e7:07:d5;CMTS-MAC=00:01:5c:ab:76:96;CM-QOS=1.1;CM-VER=3.1;"
10/17/2020 12:40820005003"Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=a8:97:cd:e7:07:d5;CMTS-MAC=00:01:5c:ab:76:96;CM-QOS=1.1;CM-VER=3.1;"
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Expert

Re: Unstable Signal after switching to Gigabit service

The SNR's from channels 25 on are too low / out of spec. You may want to get another tech visit to check for noise ingress at those frequencies. There is also way too much variation in the downstream channel power levels (from the weakest to the strongest). Good luck !



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