CyberVulpes's profile

Visitor

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7 Messages

Sat, Sep 11, 2021 5:24 PM

Internet slow downs, disconnects, general issues

Internet is going to single-digit download speeds as per ookla and xfinity speedtests, assuming the pages even load.

This has been going on three days now. I chatted with an agent who, after over an hour, managed to get my speed back somewhere approaching DSL era. Maybe it was just coincidental timing.

I did see a telecom box open on my street, and a temporary issue notice for like an hour on the outage map with no outage reported.

Modem: Motorola MB8600
Router: Netgear R6080

Modem event log is full of Warning(5) and Notice(6) 

Channel Lock Status Modulation Channel ID Freq. (MHz) Pwr (dBmV) SNR (dB) Corrected Uncorrected
   1 Locked QAM256 41 675.0 -6.8 37.4 0 0
   2 Locked QAM256 13 495.0 -4.6 38.8 0 0
   3 Locked QAM256 14 507.0 -4.9 38.9 0 0
   4 Locked QAM256 15 513.0 -4.9 36.8 0 0
   5 Locked QAM256 16 519.0 -5.1 38.0 0 0
   6 Locked QAM256 17 525.0 -5.1 38.8 0 0
   7 Locked QAM256 18 531.0 -5.1 38.7 0 0
   8 Locked QAM256 19 543.0 -5.6 38.6 0 0
   9 Locked QAM256 20 549.0 -5.9 37.5 0 0
   10 Locked QAM256 21 555.0 -5.9 38.2 0 0
   11 Locked QAM256 22 561.0 -6.2 38.3 0 0
   12 Locked QAM256 23 567.0 -6.6 38.1 0 0
   13 Locked QAM256 24 573.0 -6.2 38.3 0 0
   14 Locked QAM256 25 579.0 -6.4 38.1 0 0
   15 Locked QAM256 26 585.0 -6.5 38.0 0 0
   16 Locked QAM256 27 591.0 -6.8 37.9 0 0
   17 Locked QAM256 28 597.0 -7.1 37.8 0 0
   18 Locked QAM256 29 603.0 -7.1 37.9 0 0
   19 Locked QAM256 30 609.0 -7.3 37.6 0 0
   20 Locked QAM256 31 615.0 -7.2 37.8 0 0
   21 Not Locked QAM256 32 621.0 -6.9 0.0 2331003 0
   22 Not Locked QAM256 33 627.0 -7.0 0.0 1334775 0
   23 Locked QAM256 34 633.0 -6.9 34.0 177771142 510734975
   24 Locked QAM256 35 639.0 -7.1 36.8 17322219 6365368
   25 Locked QAM256 36 645.0 -6.9 37.1 0 0
   26 Locked QAM256 37 651.0 -6.6 37.2 0 0
   27 Locked QAM256 38 657.0 -6.6 37.6 0 0
   28 Locked QAM256 39 663.0 -6.3 37.9 0 0
   29 Locked QAM256 40 669.0 -6.7 37.8 0 0
   30 Locked QAM256 42 681.0 -7.1 37.5 0 0
   31 Locked QAM256 43 687.0 -7.9 37.4 0 0
   32 Locked QAM256 44 693.0 -7.9 37.4 0 0
   33 Locked OFDM PLC 159 722.0 -6.8 0.0 1308036821 460844847

Channel Lock Status Channel Type Channel ID Symb. Rate (Ksym/sec) Freq. (MHz) Pwr (dBmV)
   1 Locked SC-QAM 1 5120 16.4 53.5
   2 Locked SC-QAM 2 5120 22.8 56.0
   3 Locked SC-QAM 3 5120 29.2 57.0
   4 Locked SC-QAM 4 5120 35.6 54.5
   5 Locked SC-QAM 5 1280 39.6 49.0

Responses

Accepted Solution

EG

Expert

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89.6K Messages

1 m ago

@CyberVulpes 

The upstream power is too high / out of spec and the downstream power is on the weak side as well. That can cause random disconnects, spontaneous re-booting of the modem, speed, packet loss, latency problems, and the un-bonding of channels.

In an 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 5-1000 MHz, bi-directional, and no gold colored garbage from Radio Shack, Home Depot, Target, etc. Splitters should be swapped with known to be good / new ones to test.

Also check the coax cable for any damage such as cuts, nicks, kinks, sharp bends, etc.

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.


Good luck with it !

Visitor

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7 Messages

@EG thank you for your assistance, I had seen you mention splitters so I ruled that out. A tech was assigned, they resolved it. Something in the junction box, he mentioned. Recommended I go out and get a high quality shielded coax cable for the wall>modem connection to reduce any interference.

Feel free to close thread.

EG

Expert

 • 

89.6K Messages

@CyberVulpes

For curiosity, would you mind posting what the signal stats look like now please ? 

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I am a Customer Expert volunteering my time to help other customers here in the Forums.
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Visitor

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7 Messages

Sorry about the delay, here you are. Much more stable now.

Channel ID Lock Status Modulation Frequency Power SNR/MER Corrected Uncorrectables
1 Locked QAM256 423000000 Hz -4 dBmV 39 dB 0 0
2 Locked QAM256 429000000 Hz -4 dBmV 39 dB 41 0
3 Locked QAM256 435000000 Hz -5 dBmV 39 dB 2150 1
4 Locked QAM256 441000000 Hz -4 dBmV 39 dB 0 0
5 Locked QAM256 447000000 Hz -4 dBmV 39 dB 0 0
6 Locked QAM256 453000000 Hz -4 dBmV 39 dB 0 0
7 Locked QAM256 459000000 Hz -4 dBmV 39 dB 0 0
8 Locked QAM256 465000000 Hz -4 dBmV 39 dB 0 0
9 Locked QAM256 471000000 Hz -4 dBmV 39 dB 0 0
10 Locked QAM256 477000000 Hz -5 dBmV 39 dB 0 0
11 Locked QAM256 483000000 Hz -5 dBmV 38 dB 0 0
12 Locked QAM256 489000000 Hz -5 dBmV 39 dB 0 0
13 Locked QAM256 495000000 Hz -5 dBmV 38 dB 0 0
14 Locked QAM256 507000000 Hz -5 dBmV 38 dB 0 0
15 Locked QAM256 513000000 Hz -5 dBmV 38 dB 0 0
16 Locked QAM256 519000000 Hz -5 dBmV 38 dB 0 0
17 Locked QAM256 525000000 Hz -6 dBmV 38 dB 0 0
18 Locked QAM256 531000000 Hz -6 dBmV 38 dB 0 0
19 Locked QAM256 543000000 Hz -6 dBmV 38 dB 0 0
20 Locked QAM256 549000000 Hz -6 dBmV 38 dB 0 0
21 Locked QAM256 555000000 Hz -6 dBmV 38 dB 0 0
22 Locked QAM256 561000000 Hz -7 dBmV 38 dB 0 0
23 Locked QAM256 567000000 Hz -7 dBmV 38 dB 0 0
24 Locked QAM256 573000000 Hz -6 dBmV 38 dB 0 0
25 Locked QAM256 579000000 Hz -7 dBmV 38 dB 0 0
26 Locked QAM256 585000000 Hz -7 dBmV 37 dB 0 0
27 Locked QAM256 591000000 Hz -7 dBmV 37 dB 0 0
28 Locked QAM256 597000000 Hz -7 dBmV 37 dB 0 0
29 Locked QAM256 603000000 Hz -7 dBmV 37 dB 0 0
30 Locked QAM256 609000000 Hz -7 dBmV 37 dB 0 0
31 Locked QAM256 615000000 Hz -7 dBmV 37 dB 0 0
32 Locked QAM256 621000000 Hz -7 dBmV 37 dB 0 0
159 Locked OFDM PLC 722000000 Hz -7 dBmV 36 dB 1632306545 0

Channel ID Lock Status US Channel Type Frequency Width Power
1 Locked SC-QAM 16400000 Hz 6400000 45.0 dBmV
2 Locked SC-QAM 22800000 Hz 6400000 45.0 dBmV
3 Locked SC-QAM 29200000 Hz 6400000 44.5 dBmV
4 Locked SC-QAM 35600000 Hz 6400000 44.5 dBmV
5 Locked SC-QAM 39600000 Hz 1600000 42.0 dBmV

(edited)

Visitor

 • 

7 Messages

1 m ago

Can't figure out how to mark this public so I can get other peoples' eyes on this

EG

Expert

 • 

89.6K Messages

@CyberVulpes

You need to redact the CM MAC and the CMTS MAC addresses, I can then mark it public for you. They are considered to be personal information. Personally identifying information is a violation of their forum guidelines. The forum bot will not allow your post to be seen publically.  

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? Please mark an Accepted Answer!tick

Visitor

 • 

7 Messages

@EG

Thank you, I went and removed that table.

XfinityBrie

Official Employee

 • 

371 Messages

1 m ago

Hi there @CyberVulpes thank you for reaching out to our Xfinity Forums. So I know you mentioned this has been going on a few days now--have this issue ever cropped up in the past by chance? Any discernable patterns?

Visitor

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7 Messages

@XfinityBrie no pattern, but a tech just arrived and resolved it. 

XfinityBrie

Official Employee

 • 

371 Messages

Thank you for letting me know! I saw you and @EG were also chatting, happy to hear everything was resolved and we're back on target. Give us a shout if you ever need anything--myself and the Experts are always happy to help. 

I am an Official Xfinity Employee.
Official Employees are from multiple teams within Xfinity: CARE, Product, Leadership.
We ask that you post publicly so people with similar questions may benefit from the conversation.
Was your question answered? Please, mark a reply as the Accepted Answer.tick
EG

Expert

 • 

89.6K Messages

1 m ago

The upstream power is much better. The downstream is still a bit on the weak side. It could be even better. Hope things hold up for you ! Good luck ! 🙂

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