U

Visitor

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3 Messages

Tue, Jan 25, 2022 6:21 PM

Motorola MB8611 reporting huge amounts of Corrected and Uncorrected Errors & Speed Flucations

Recently upgraded my home connection speed to the 900/20 plan.  When I made the switch I was informed to upgrade my cable modem from my older model to be compatible with the new speed.

Now my connection is unstable.  The speed will fluctuate wildly throughout the day seemingly at random.  It will drop as low as 15-45 down, then within 3-5 minutes be back to 600+ down.  (Tests run through independent speed test sites using a wired connection).

Restarting the modem (either manually or through the Xfinity website) seems to do nothing.

Here are the current connection stats since the last restart.  Modem has only been up and running for 15 hours.  (Event log is also filled with notices and warnings).

 Downstream Bonded Channels  
  
   Channel Lock Status Modulation Channel ID Freq. (MHz) Pwr (dBmV) SNR (dB) Corrected Uncorrected
   1 Locked QAM256 5 543.0 -6.9 39.2 154 85
   2 Locked QAM256 2 525.0 -5.6 41.4 41 11
   3 Locked QAM256 3 531.0 -7.5 40.3 249 83
   4 Locked QAM256 4 537.0 -4.9 37.9 41 28
   5 Locked QAM256 6 555.0 -4.1 31.1 159268030 422859
   6 Locked QAM256 7 561.0 -6.4 27.7 495878760 20688252
   7 Locked QAM256 8 567.0 -4.0 34.2 16 0
   8 Locked QAM256 9 573.0 -5.8 30.7 48268 4312
   9 Locked QAM256 10 579.0 -5.6 39.3 5 0
   10 Locked QAM256 11 585.0 -6.2 40.6 65 26
   11 Locked QAM256 12 591.0 -6.9 40.3 167 102
   12 Locked QAM256 13 597.0 -5.5 33.1 819 26
   13 Locked QAM256 14 603.0 -7.5 27.0 2760931 2804352
   14 Locked QAM256 15 609.0 -5.7 37.9 2980 1962
   15 Locked QAM256 16 615.0 -6.4 40.8 33 4
   16 Locked QAM256 17 621.0 -6.2 40.1 43 7
   17 Locked QAM256 18 627.0 -6.3 38.3 36 1
   18 Locked QAM256 19 633.0 -7.4 39.6 11 0
   19 Locked QAM256 20 639.0 -5.8 40.1 0 0
   20 Locked QAM256 21 645.0 -8.2 39.5 329 94
   21 Locked QAM256 22 651.0 -7.3 40.1 49 0
   22 Locked QAM256 23 657.0 -6.8 40.5 12 0
   23 Locked QAM256 24 663.0 -8.1 39.7 68 92
   24 Locked QAM256 25 669.0 -5.4 41.2 0 0
   25 Locked QAM256 26 675.0 -6.8 39.7 2 0
   26 Locked QAM256 27 681.0 -5.2 41.5 30 1
   27 Locked QAM256 28 687.0 -7.0 40.5 85 42
   28 Locked QAM256 29 693.0 -6.9 40.5 47 25
   29 Locked QAM256 30 699.0 -6.2 41.0 35 48
   30 Locked QAM256 31 705.0 -8.5 39.6 3756 8585
   31 Locked QAM256 32 711.0 -7.9 40.0 4147 6380
   32 Locked OFDM PLC 37 762.0 -8.3 37.0 384425736 57042


   Upstream Bonded Channels  
  
   Channel Lock Status Channel Type Channel ID Symb. Rate (Ksym/sec) Freq. (MHz) Pwr (dBmV)
   1 Locked SC-QAM 9 5120 35.6 47.3
   2 Locked SC-QAM 10 5120 29.2 53.5
   3 Locked SC-QAM 11 5120 22.8 51.8
   4 Locked SC-QAM 12 5120 16.4 50.5

Event log warnings all read

13:19:22
Tue Jan 25 2022
  Warning (5)   MDD message timeout
EG

Expert

 • 

93.8K Messages

4 m ago

The upstream power is too high (already out of spec on channel #2) and it may be intermittently fluctuating even higher out of spec. And the downstream power is on the low weak side. 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

 • 

3 Messages

@EG​ Moved the router to be directly on the line coming from outside the house (so no splitters, no splice).

Only been running for 5 minutes and already loads of corrected and uncorrected.

  Connection Status    
   System Up Time 0 days 00h:05m:30s  
  
   Network Access Allowed  
  


   Downstream Bonded Channels  
  
   Channel Lock Status Modulation Channel ID Freq. (MHz) Pwr (dBmV) SNR (dB) Corrected Uncorrected
   1 Locked QAM256 5 543.0 -3.5 39.9 13 0
   2 Locked QAM256 1 519.0 -5.1 40.9 32 0
   3 Locked QAM256 2 525.0 -2.0 42.3 5 0
   4 Locked QAM256 3 531.0 -4.6 41.3 37 6
   5 Locked QAM256 4 537.0 -2.3 38.6 6 0
   6 Locked QAM256 6 555.0 -0.7 31.0 17155 0
   7 Locked QAM256 7 561.0 -3.1 29.6 15099 11
   8 Locked QAM256 8 567.0 -1.2 36.5 33 0
   9 Locked QAM256 9 573.0 -2.2 32.6 31 0
   10 Locked QAM256 10 579.0 -2.6 40.4 32 0
   11 Locked QAM256 11 585.0 -3.0 41.7 31 0
   12 Locked QAM256 12 591.0 -3.3 41.5 0 0
   13 Locked QAM256 13 597.0 -2.7 32.1 0 0
   14 Locked Unknown 14 603.0 -3.8 0.0 173 0
   15 Locked QAM256 15 609.0 -2.6 38.8 12 0
   16 Locked QAM256 16 615.0 -3.2 41.8 0 0
   17 Locked QAM256 17 621.0 -2.7 41.0 0 0
   18 Locked QAM256 18 627.0 -3.5 39.6 0 0
   19 Locked QAM256 19 633.0 -3.9 41.2 0 0
   20 Locked QAM256 33 495.0 -1.7 42.5 28 16
   21 Locked QAM256 34 501.0 -6.0 40.5 33 7
   22 Locked QAM256 35 507.0 -2.6 42.3 33 0
   23 Locked QAM256 36 513.0 -3.4 41.6 30 14
   24 Locked OFDM PLC 37 762.0 -5.3 37.5 1828812 327
   25 Locked QAM256 38 471.0 -5.2 41.1 36 0
   26 Locked QAM256 39 477.0 -3.4 41.9 33 10
   27 Locked QAM256 40 483.0 -4.0 40.5 28 17
   28 Locked QAM256 41 489.0 -5.5 40.9 28 17
   29 Locked QAM256 42 447.0 -0.7 42.9 0 0
   30 Locked QAM256 43 453.0 -1.5 42.3 4 0
   31 Locked QAM256 44 459.0 -3.5 41.7 31 12
   32 Locked QAM256 45 465.0 -1.3 41.9 24 0


   Upstream Bonded Channels  
  
   Channel Lock Status Channel Type Channel ID Symb. Rate (Ksym/sec) Freq. (MHz) Pwr (dBmV)
   1 Locked SC-QAM 9 5120 35.6 46.3
   2 Locked SC-QAM 10 5120 29.2 52.5
   3 Locked SC-QAM 11 5120 22.8 51.3
   4 Locked SC-QAM 12 5120 16.4 49.3


   Downstream Frequency Setting    
   Downstream Frequency Select   
  


EG

Expert

 • 

93.8K Messages

It's still too high. If there is nothing more that can be done to improve the connection, you may want to consider getting a tech out to investigate / correct.

Bear in mind that if the premises facing techs can not find or fix a problem at your home, it is they who are responsible for escalating it to their line / network / maintenance dept. techs. The problem may lie beyond your home in the local neighborhood infrastructure somewhere but it is their S.O.P. to start at the home.


Good luck !

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Visitor

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3 Messages

Looks like I'll need a tech out.  Probably need to wait for the snow to melt.

EG

Expert

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93.8K Messages

4 m ago

Please post back with how things turn out.

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