Community Forum

0.5Mbps slow internet - SNR / signal issues - call tech? (logs included)

New Poster

0.5Mbps slow internet - SNR / signal issues - call tech? (logs included)

My internet has become awful slow recently - 0.5 to 2Mbps.   I dont' see anything amiss in cabling in house, it's a super straight shot.   Modem specs look bad far as I can tell.   Call a tech to check outside line?

 

CM500 16x4 modem, current firmware and no indications of functionality issues BTW

 

img1.jpgimg2.jpg

New Poster

Re: 0.5Mbps slow internet - SNR / signal issues - call tech? (logs included)

In case you guys can't see images of my logs either:

Channel  Lock Status  Modulation  Ch ID  Frequency  Power  SNR  Correctables  Uncorrectables 
1 Locked QAM256 21 621000000 Hz -10.7 dBmV 29.1 dB 42149841 32886
2 Locked QAM256 11 561000000 Hz 0.6 dBmV 35.8 dB 0 0
3 Locked QAM256 12 567000000 Hz 0.1 dBmV 35.5 dB 0 0
4 Locked QAM256 13 573000000 Hz -0.9 dBmV 34.8 dB 7 0
5 Locked QAM256 14 579000000 Hz -2 dBmV 34.1 dB 21 0
6 Locked QAM256 15 585000000 Hz -3.2 dBmV 33.7 dB 118 0
7 Locked QAM256 16 591000000 Hz -4.2 dBmV 33 dB 379 0
8 Locked QAM256 17 597000000 Hz -4.8 dBmV 32.6 dB 2018 0
9 Locked QAM256 18 603000000 Hz -5.7 dBmV 32 dB 9993 0
10 Locked QAM256 19 609000000 Hz -7.2 dBmV 31.3 dB 132230 0
11 Locked QAM256 20 615000000 Hz -8.8 dBmV 30.3 dB 3466569 14
12 Locked QAM256 22 627000000 Hz -12.4 dBmV 27.6 dB 243298530 33232375
13 Locked QAM256 23 633000000 Hz -13.3 dBmV 26.5 dB 217243375 13238773
14 Not Locked Unknown 24 639000000 Hz 0.0 dBmV 0.0 dB 0 0
15 Not Locked Unknown 25 645000000 Hz 0.0 dBmV 0.0 dB 0 0
16 Not Locked Unknown 26 651000000 Hz 0.0 dBmV 0.0 dB 0 0
Channel  Lock Status  US Channel Type  Channel ID  Symbol Rate  Frequency  Power 
1 Locked ATDMA 8 5120 Ksym/sec 16600000 Hz 36 dBmV
2 Locked ATDMA 5 5120 Ksym/sec 35800000 Hz 34.8 dBmV
3 Locked ATDMA 6 5120 Ksym/sec 29400000 Hz 35.8 dBmV
4 Locked ATDMA 7 5120 Ksym/sec 23000000 Hz 36.3 dBmV

 

Diamond Problem Solver

Re: 0.5Mbps slow internet - SNR / signal issues - call tech? (logs included)

If you’ve done all you can on your end, than yes have a tech out. Those levels and SNR are all over the place. If you need assistance scheduling one let us know.

I am a Retired Official Comcast Employee
We ask that you post publicly so people with similar questions may benefit from the conversation.
Was your question answered? Mark a post as the Best Answer!
Highlighted
Expert

Re: 0.5Mbps slow internet - SNR / signal issues - call tech? (logs included)

The downstream stream power and the SNR is low / out of spec on most of the downstream channels and the higher frequency ones don't seem to be locking. That can cause random disconnects, spontaneous re-booting of the modem, speed, packet loss, latency problems, and the unbonding 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.



I am not a Comcast Employee.
I am a Customer Expert volunteering my time to help other customers here in the Forums.
We ask that you post publicly so people with similar questions may benefit from the conversation.
Was your question answered? Mark the post as Best Answer!