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Cable Modem High Error Status

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Cable Modem High Error Status

I have a Arris SB6190, with the following version: HW=3: SW =9.1.103AA65L. I have been intermittant very slow data downloads using Xfinity Speed Test. After resetting the modem (power-off) and  logging into the modems web view, there are no uncorrectable errors and the signal levels are between 4.9dBmv and 9.1dBmv and the download speed is as predicted (about 300-325mbps). After about a few hours, the speed deteriorates, there is about 35,000-72,000 uncorrfectable errors for each of 32 channels and the signal levels or some of the channels are -1.42dBmv. Is this a faulty modem or line or other?

Thanks

 

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Expert

Re: Cable Modem High Error Status

It's more likely to be an intermittent line / signal / connection quality problem. Please also post the upstream power level and the SNR figures. Can you please post screenshots of all of the modems signal stat values both when they are good and not good .



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Re: Cable Modem High Error Status

This is the best of could do. it shows a bad run. A good run is about the same, but with zero Corrected and Uncorrectables

 

 

 

 
Downstream Bonded Channels
Channel Lock Status Modulation Channel ID Frequency Power SNR Corrected Uncorrectables
1 Locked 256QAM 15 585.00 MHz 5.00 dBmV 40.37 dB 174762 2827580
2 Locked 256QAM 1 495.00 MHz 4.20 dBmV 40.37 dB 159560 2737944
3 Locked 256QAM 2 501.00 MHz 3.80 dBmV 40.95 dB 161099 2743373
4 Locked 256QAM 3 507.00 MHz 3.60 dBmV 40.37 dB 160289 2731856
5 Locked 256QAM 4 513.00 MHz 3.60 dBmV 40.95 dB 162095 2717170
6 Locked 256QAM 5 519.00 MHz 3.60 dBmV 40.37 dB 163442 2806488
7 Locked 256QAM 6 525.00 MHz 3.70 dBmV 40.37 dB 160387 2724858
8 Locked 256QAM 7 531.00 MHz 3.80 dBmV 40.95 dB 157822 2731051
9 Locked 256QAM 8 537.00 MHz 4.00 dBmV 40.37 dB 160296 2723474
10 Locked 256QAM 9 543.00 MHz 4.30 dBmV 40.95 dB 168587 2726577
11 Locked 256QAM 10 549.00 MHz 4.90 dBmV 40.95 dB 175691 2670215
12 Locked 256QAM 11 561.00 MHz 5.90 dBmV 40.37 dB 185060 2774767
13 Locked 256QAM 12 567.00 MHz 6.50 dBmV 40.95 dB 164570 2831644
14 Locked 256QAM 13 573.00 MHz 6.20 dBmV 40.37 dB 158664 2849305
15 Locked 256QAM 14 579.00 MHz 6.10 dBmV 40.95 dB 160531 2845473
16 Locked 256QAM 16 591.00 MHz 4.60 dBmV 40.37 dB 181750 2806593
17 Locked 256QAM 17 597.00 MHz 3.60 dBmV 40.95 dB 178067 2770145
18 Locked 256QAM 18 603.00 MHz 3.20 dBmV 40.37 dB 165455 2763651
19 Locked 256QAM 19 609.00 MHz 2.40 dBmV 38.98 dB 160694 2742866
20 Locked 256QAM 20 615.00 MHz 2.60 dBmV 40.37 dB 159309 2740193
21 Locked 256QAM 21 621.00 MHz 2.30 dBmV 40.37 dB 170111 2761485
22 Locked 256QAM 22 627.00 MHz 3.40 dBmV 40.37 dB 185064 2849094
23 Locked 256QAM 23 633.00 MHz 4.30 dBmV 38.98 dB 228752 2867569
24 Locked 256QAM 24 639.00 MHz 8.40 dBmV 38.61 dB 250534 3460560
25 Locked 256QAM 26 645.00 MHz 11.20 dBmV 38.90 dB 1077576 112933
26 Locked 256QAM 27 651.00 MHz 7.40 dBmV 35.90 dB 2038638 265255
27 Locked 256QAM 28 657.00 MHz 2.60 dBmV 38.90 dB 8521 16208
28 Locked 256QAM 29 663.00 MHz 1.10 dBmV 38.60 dB 1677 15045
29 Locked 256QAM 30 669.00 MHz 1.40 dBmV 38.90 dB 1214 10840
30 Locked 256QAM 31 675.00 MHz -1.30 dBmV 36.90 dB 37701 19618
31 Locked 256QAM 32 681.00 MHz -0.50 dBmV 37.60 dB 1913 12141
32 Locked 256QAM 33 687.00 MHz 0.90 dBmV 38.90 dB 1357 11686

 

 
Upstream Bonded Channels
Channel Lock Status US Channel Type Channel ID Symbol Rate Frequency Power
1 Locked ATDMA 2 5120 kSym/s 30.10 MHz 39.00 dBmV
2 Locked ATDMA 4 5120 kSym/s 17.30 MHz 38.75 dBmV
3 Locked ATDMA 3 5120 kSym/s 23.70 MHz 38.75 dBmV
4 Locked ATDMA 1 5120 kSym/s 36.50 MHz 39.00 dBmV
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Re: Cable Modem High Error Status

also a good run does not have low power. They range from 4.8 to 9.10dBmV

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Re: Cable Modem High Error Status


@Danbar wrote:

also a good run does not have low power. They range from 4.8 to 9.10dBmV


What about the upstream stats on a good and a bad "run" ?



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Re: Cable Modem High Error Status

The good and bad upstream are identical: power levels for a good are all 38.75. As seen above, a bad run dips to 38.75

Thanks again

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Expert

Re: Cable Modem High Error Status

Alright well something is going on as there is a very wide variation with the downstream power levels of the channels ! Should be no more than a 3-4 dB variation. See if anything here helps / applies;

 

In a self troubleshooting effort to try to obtain better connectivity, 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.



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Re: Cable Modem High Error Status

You are so helpful and I am most appreciative!!! The following is my configuration:

1. The cable from the street is connected to a barrier connector with a ground. Just straight through....

2. From the barrier connector, the cable goes to a 1 to 3 splitter of the following characteristics:

2.1. "Extreme Broadband Engineering" model BDS103HB; 3-way balanced Digital Splitter

2.2 Each leg is marked "Out -5.5db"

2.3 One leg goes to the cable modem

2.4 The second leg goes directly to the X1 DVR

2.5 The third leg goes to a multi-leg splitter for subsequent connection to 5 DTA's and to the voice modem.

 

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Expert

Re: Cable Modem High Error Status

Have you tried refreshing / checking / cleaning / tightening any of the connections leading to the modem ?



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Re: Cable Modem High Error Status

Everything is brand spanking new. Called Customer service and did observed  some aberrations on their end.  So I scheduled a technican to take a look at things. 

Thanks again, you have been so helpful!!

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Re: Cable Modem High Error Status

That was going to be my next suggestion. Good luck with it ! 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.

Please post back with how things turn out.



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Re: Cable Modem High Error Status

A technician checked the signal level and my splitter configuration. He forced a refresh to the modem, ensuring the modem properly received a complete configuration/firmware refresh. He then removed my old amplifier for the DTA and old splitters and replaced them with a completely new configuration/ equipment. Padded down the input signal down a bit and checked the signals across the frequency spectrum with an analyzer. Also, he reterminated all my connections. I now have been running with zero "uncorrectables", 360mbps download speeds. The technician did a great job! And I thank you for your help in the diagnoses. 

 

 

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Re: Cable Modem High Error Status

Quite welcome ! Hope things hold up for you !


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