BELL5's profile

New Poster

 • 

4 Messages

Monday, October 12th, 2020 1:00 PM

Closed

Progressively worse connection - any suggestions?

For over 3 months my connectivity has progressively gotten worse, it started with sporadict drops and now it's multiple times a day. I've tried; replacing my modem, replacing my router and having an Comcast technician test to my wall outlet.

 

It's gotten to a point that we are struggling to keep a connection during work team meetings. 

 

Does anyone have any ideas on how I can get this resolved?

 

 

There are multiple critical enteries in my log :

 

SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;
Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;

Started Unicast Maintenance Ranging - No Response received - T3 time-out;

 

 
 
Apply               Cancel     
Frequency start Value
This field below allows you to modify the frequency the cable modem start with its scan during initialization and registration. Enter the new start frequency and restart the cable modem for it to take effect.
Starting Frequency
 

Startup Procedure

ProcedureStatusComment
Acquire Downstream Channel525000000 HzLocked
Connectivity StateOKOperational
Boot StateOKOperational
SecurityEnabledBPI+
IP Provisioning ModeHonor MDDhonorMdd(4)
 

Downstream Bonded Channels

ChannelLock StatusModulationChannel IDFrequencyPowerSNRCorrectablesUncorrectables
1LockedQAM25620525000000 Hz1.8 dBmV42.3 dB50
2LockedQAM2564411000000 Hz-0.1 dBmV41.9 dB00
3LockedQAM2565417000000 Hz0.1 dBmV42 dB00
4LockedQAM2566435000000 Hz0.3 dBmV42 dB00
5LockedQAM2567441000000 Hz0.1 dBmV41.9 dB00
6LockedQAM2568453000000 Hz0.7 dBmV42.3 dB00
7LockedQAM2569459000000 Hz0.8 dBmV42.3 dB00
8LockedQAM25610465000000 Hz0.8 dBmV42.3 dB00
9LockedQAM25611471000000 Hz0.8 dBmV42.2 dB00
10LockedQAM25612477000000 Hz0.8 dBmV42.1 dB00
11LockedQAM25613483000000 Hz1 dBmV42.2 dB50
12LockedQAM25614489000000 Hz1.3 dBmV42.4 dB10
13LockedQAM25615495000000 Hz1.4 dBmV42.3 dB00
14LockedQAM25616501000000 Hz1.5 dBmV42.3 dB20
15LockedQAM25617507000000 Hz1.6 dBmV42.3 dB10
16LockedQAM25618513000000 Hz1.6 dBmV42.3 dB90
17LockedQAM25619519000000 Hz1.8 dBmV42.3 dB50
18LockedQAM25621531000000 Hz1.8 dBmV42.2 dB60
19LockedQAM25622537000000 Hz1.8 dBmV42.2 dB60
20LockedQAM25623543000000 Hz1.9 dBmV42.3 dB40
21LockedQAM25624549000000 Hz1.9 dBmV42.3 dB60
22LockedQAM25625555000000 Hz2.1 dBmV42.3 dB40
23LockedQAM25626561000000 Hz2.2 dBmV42.3 dB70
24LockedQAM25627567000000 Hz2.1 dBmV42.3 dB50
25LockedQAM25628573000000 Hz2 dBmV42.2 dB60
26LockedQAM25629579000000 Hz1.8 dBmV42 dB60
27LockedQAM25630585000000 Hz1.7 dBmV41.9 dB100
28LockedQAM25631591000000 Hz1.6 dBmV41.8 dB50
29LockedQAM25632597000000 Hz1.7 dBmV41.7 dB50
30LockedQAM25633603000000 Hz1.6 dBmV42 dB70
31LockedQAM25634609000000 Hz1.3 dBmV41.9 dB50
32Not LockedUnknown00 Hz0.0 dBmV0.0 dB00
 

Upstream Bonded Channels

ChannelLock StatusUS Channel TypeChannel IDSymbol RateFrequencyPower
1LockedATDMA25120 Ksym/sec22800000 Hz50.5 dBmV
2LockedATDMA35120 Ksym/sec29200000 Hz49.3 dBmV
3LockedATDMA45120 Ksym/sec35600000 Hz47.8 dBmV
4LockedATDMA51280 Ksym/sec40400000 Hz45 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
 

Downstream OFDM Channels

ChannelLock
Status
Modulation /
Profile ID
Channel
ID
FrequencyPowerSNR /
MER
Active Subcarrier
Number Range
Unerrored
Codewords
Correctable
Codewords
Uncorrectable
Codewords
1Locked0 ,1 ,2 ,348722000000 Hz3.5 dBmV41.7 dB1228 ~ 28675314127347260
2Not Locked000 Hz0 dBmV0.0 dB0 ~ 4095000
 

Upstream OFDMA Channels

ChannelLock StatusModulation / Profile IDChannel IDFrequencyPower
1Not Locked000 Hz0 dBmV
2Not Locked000 Hz0 dBmV
 

Extended Upstream Transmit PowerEnable Extended Upstream Transmit Power

 

Current System Time:Mon Oct 12 14:20:55 2020System Up Time:12:31:13

This conversation is no longer open for comments or replies and is no longer visible to community members.

Expert

 • 

111.5K Messages

5 years ago

The upstream power is high 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 get the techs re-involved until it is fixed properly. Good luck !

Expert

 • 

111.5K Messages

5 years ago

It's too high. "Attenuators" can't lower the upstream power, they make it higher ! Attenuators lower the downstream power. Is that what you meant to say ?

New Poster

 • 

4 Messages

5 years ago

EG, thank you for the reply and the troubleshooting steps.

 

Last week the Comcast technician did place an attenuator to lower the upstream power. 

New Poster

 • 

4 Messages

5 years ago

Now I'm second guessing the conversation. I recall he said something was too high and that he placed something on the coax to correct it. 

Expert

 • 

111.5K Messages

5 years ago

Try removing it and repost the stats.

New Poster

 • 

4 Messages

5 years ago

I couldn't find the cable that the tech had placed the attenuator on, there are half a dozen coax cables in my attic for some reason!

 

Like clockwork my connection went down again. It seems to happen around 1pm - 2pm CST everyday and then again later in the evening. 

 

 

 
Apply               Cancel     
Frequency start Value
This field below allows you to modify the frequency the cable modem start with its scan during initialization and registration. Enter the new start frequency and restart the cable modem for it to take effect.
Starting Frequency
 

Startup Procedure

ProcedureStatusComment
Acquire Downstream Channel525000000 HzLocked
Connectivity StateOKOperational
Boot StateOKOperational
SecurityEnabledBPI+
IP Provisioning ModeHonor MDDhonorMdd(4)
 

Downstream Bonded Channels

ChannelLock StatusModulationChannel IDFrequencyPowerSNRCorrectablesUncorrectables
1LockedQAM25620525000000 Hz1.8 dBmV42.5 dB1014833
2LockedQAM2564411000000 Hz-0.1 dBmV42.1 dB2284859
3LockedQAM2565417000000 Hz0.1 dBmV42.2 dB2297899
4LockedQAM2566435000000 Hz0.3 dBmV42.2 dB1981840
5LockedQAM2567441000000 Hz0 dBmV42.1 dB1748883
6LockedQAM2568453000000 Hz0.6 dBmV42.5 dB1697887
7LockedQAM2569459000000 Hz0.7 dBmV42.5 dB2042853
8LockedQAM25610465000000 Hz0.7 dBmV42.4 dB1536910
9LockedQAM25611471000000 Hz0.7 dBmV42.4 dB1571929
10LockedQAM25612477000000 Hz0.7 dBmV42.3 dB1524877
11LockedQAM25613483000000 Hz0.8 dBmV42.3 dB1654835
12LockedQAM25614489000000 Hz1.2 dBmV42.5 dB1477885
13LockedQAM25615495000000 Hz1.2 dBmV42.5 dB1380857
14LockedQAM25616501000000 Hz1.4 dBmV42.5 dB1214867
15LockedQAM25617507000000 Hz1.5 dBmV42.5 dB934817
16LockedQAM25618513000000 Hz1.5 dBmV42.5 dB1211848
17LockedQAM25619519000000 Hz1.7 dBmV42.5 dB1225845
18LockedQAM25621531000000 Hz1.8 dBmV42.4 dB902814
19LockedQAM25622537000000 Hz1.9 dBmV42.4 dB771799
20LockedQAM25623543000000 Hz2 dBmV42.5 dB725753
21LockedQAM25624549000000 Hz2.1 dBmV42.5 dB733785
22LockedQAM25625555000000 Hz2.2 dBmV42.5 dB637729
23LockedQAM25626561000000 Hz2.3 dBmV42.5 dB674731
24LockedQAM25627567000000 Hz2.3 dBmV42.5 dB588761
25LockedQAM25628573000000 Hz2.2 dBmV42.4 dB654798
26LockedQAM25629579000000 Hz2 dBmV42.2 dB845738
27LockedQAM25630585000000 Hz1.9 dBmV42.1 dB923722
28LockedQAM25631591000000 Hz1.8 dBmV42 dB756786
29LockedQAM25632597000000 Hz1.9 dBmV41.9 dB744750
30LockedQAM25633603000000 Hz1.8 dBmV42.2 dB772804
31LockedQAM25634609000000 Hz1.4 dBmV42.1 dB1002822
32Not LockedUnknown00 Hz0.0 dBmV0.0 dB00
 

Upstream Bonded Channels

ChannelLock StatusUS Channel TypeChannel IDSymbol RateFrequencyPower
1LockedATDMA25120 Ksym/sec22800000 Hz50.3 dBmV
2LockedATDMA35120 Ksym/sec29200000 Hz49.3 dBmV
3LockedATDMA45120 Ksym/sec35600000 Hz48 dBmV
4LockedATDMA51280 Ksym/sec40400000 Hz45 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
 

Downstream OFDM Channels

ChannelLock
Status
Modulation /
Profile ID
Channel
ID
FrequencyPowerSNR /
MER
Active Subcarrier
Number Range
Unerrored
Codewords
Correctable
Codewords
Uncorrectable
Codewords
1Locked0 ,1 ,2 ,348722000000 Hz3.5 dBmV41.7 dB1228 ~ 2867190409849510899054396
2Not Locked000 Hz0 dBmV0.0 dB0 ~ 4095000
 

Upstream OFDMA Channels

ChannelLock StatusModulation / Profile IDChannel IDFrequencyPower
1Not Locked000 Hz0 dBmV
2Not Locked000 Hz0 dBmV
 

Extended Upstream Transmit PowerEnable Extended Upstream Transmit Power

 

Current System Time:Tue Oct 13 12:41:48 2020System Up Time:1 day 10:52:06

Expert

 • 

111.5K Messages

5 years ago

It's still too high. Perhaps it would be best to get another tech out to investigate / correct the problem. Good luck with it !

Official Employee

 • 

4.2K Messages

5 years ago

Hello @BELL5, thanks for reaching out to us on our Forums page. We appreciate you being a customer with us, and I apologize for the connection issues you have recently been experiencing. We definitely understand how important it is to have a steady and consistent connection. I can imagine how inconvenient and frustrating these connection issues must be. We would love to help! I see you have already sent me a private message and I will respond promptly. 

forum icon

New to the Community?

Start Here