U

Visitor

 • 

6 Messages

Monday, May 24th, 2021 3:18 PM

Closed

Arris SB6190 Issues

Hi folks,

Hope I can find a better avenue of support through here then going through the motion of a power cycle 5 different ways.

Most recently I've had continuous instability issue with an Arris SB6190.  Lime many folks I opted to purchase my own equipment vs. paying the monthly rental using Xfinity's modem/router combo.  In the past the xfinity unit would occasionally fail but that occurrence was seldom, and for the most part held strong.  I also had the triple play package and physical lines would use a splitter in the house feeding the internet and 3 rooms.....Again, line was stable.  I've had the Arris (~8 months) it's been frustrating.  I had a tech come out and during the line test indicated the splitter in use was reducing the signal.  Since I had no use for keeping it inline, it was removed and the signal/stability were restored.  This didn't lead to any issues with the exception of 1-2 reboots a week over the course of 2 months.  Fast forward and I'm now getting a repeat of issues encountered prior to the tech visit. The event log on the Arris keep showing T3 time-outs which leads to the modem rebooting.  This happens about 8x a day on average now.  The bottom line I've witnessed since I switched to the SB6190 is quality suffering every packet of the way.  I'm not sure I can chalk it up to the Intel Puma chips as the root cause, but hoping through showing my levels I can get some better feedback from the crowd.  Thanks in advance everyone!

Downstream Bonded Channels

Channel               Lock Status         Modulation        Channel ID          Frequency          Power                   SNR                        Corrected            Uncorrectables

1                              Locked                  256QAM              13                           471.00 MHz        0.90 dBmV          40.37 dB              11                                0

2                              Locked                  256QAM              1                              399.00 MHz        1.20 dBmV          40.95 dB              0                                0

3                              Locked                  256QAM              2                              405.00 MHz        1.30 dBmV          40.37 dB              0                                0

4                              Locked                  256QAM              3                              411.00 MHz        1.50 dBmV          40.37 dB              0                                0

5                              Locked                  256QAM              4                              417.00 MHz        1.20 dBmV          40.37 dB              6                                0

6                              Locked                  256QAM              5                              423.00 MHz        1.30 dBmV          40.37 dB              6                                0

7                              Locked                  256QAM              6                              429.00 MHz        0.90 dBmV          40.95 dB              11                                0

8                              Locked                  256QAM              7                              435.00 MHz        0.80 dBmV          40.95 dB              10                                0

9                              Locked                  256QAM              8                              441.00 MHz        0.80 dBmV          40.95 dB              10                                0

10                           Locked                  256QAM              9                              447.00 MHz        0.70 dBmV          40.37 dB              0                                0

11                           Locked                  256QAM              10                           453.00 MHz        0.90 dBmV          40.95 dB              0                                0

12                           Locked                  256QAM              11                           459.00 MHz        0.70 dBmV          40.37 dB              0                                0

13                           Locked                  256QAM              12                           465.00 MHz        0.90 dBmV          40.37 dB              0                                0

14                           Locked                  256QAM              14                           477.00 MHz        1.00 dBmV          40.37 dB              0                                0

15                           Locked                  256QAM              15                           483.00 MHz        0.90 dBmV          40.37 dB              0                                0

16                           Locked                  256QAM              16                           489.00 MHz        0.70 dBmV          40.37 dB              7                                0

17                           Locked                  256QAM              17                           495.00 MHz        0.70 dBmV          40.95 dB              0                                0

18                           Locked                  256QAM              18                           507.00 MHz        0.50 dBmV          40.37 dB              3                                0

19                           Locked                  256QAM              19                           513.00 MHz        0.40 dBmV          40.95 dB              7                                0

20                           Locked                  256QAM              20                           519.00 MHz        0.20 dBmV          40.37 dB              0                                0

21                           Locked                  256QAM              21                           525.00 MHz        0.40 dBmV          40.37 dB              0                                0

22                           Locked                  256QAM              22                           531.00 MHz        0.50 dBmV          40.95 dB              0                                0

23                           Locked                  256QAM              23                           537.00 MHz        0.40 dBmV          40.37 dB              21                                0

24                           Locked                  256QAM              24                           543.00 MHz        0.40 dBmV          40.37 dB              8                                0

25                           Locked                  256QAM              25                           555.00 MHz        0.40 dBmV          39.90 dB              0                                0

26                           Locked                  256QAM              26                           561.00 MHz        0.20 dBmV          39.50 dB              11                                0

27                           Locked                  256QAM              27                           567.00 MHz        0.20 dBmV          39.50 dB              0                                0

28                           Locked                  256QAM              28                           573.00 MHz        -0.40 dBmV        39.50 dB              0                                0

29                           Locked                  256QAM              29                           579.00 MHz        -0.10 dBmV        39.50 dB              0                                0

30                           Locked                  256QAM              30                           585.00 MHz        -0.40 dBmV        39.50 dB              0                                0

31                           Locked                  256QAM              31                           591.00 MHz        -0.30 dBmV        39.90 dB              0                                0

32                           Locked                  256QAM              32                           597.00 MHz        -0.30 dBmV        39.50 dB              0                                0

 

Channel               Lock Status         US Channel Type              Channel ID          Symbol Rate       Frequency          Power

1                              Locked                  ATDMA                                4                              5120 kSym/s      16.40 MHz          54.00 dBmV

2                              Locked                  ATDMA                                 3                              5120 kSym/s      22.80 MHz          54.00 dBmV

3                              Locked                  ATDMA                                 2                              5120 kSym/s      29.20 MHz          49.50 dBmV

4                              Locked                  ATDMA                                 1                              5120 kSym/s      35.60 MHz          51.00 dBmV

Expert

 • 

105.7K Messages

3 years ago

The upstream power is too high / out of spec. 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

 • 

6 Messages

EG, thanks for the reply, and detail.  Could you provide feedback on what defines a good power level.  I've read multiple articles/sources, and they actually vary within the window of those values I provided as good.  

In summary I have a drop line<>coupler<>home line in garage<>coupler<> home line to modem.

I removed one of the lines and the core seemed dirty and pretty extended.  I snipped it about 1-2mm back and reconnected it all.  Current upstream is  the following.

Channel               Lock Status         US Channel Type              Channel ID          Symbol Rate       Frequency          Power

1                              Locked                  ATDMA                                4                 5120 kSym/s      16.40 MHz          51.00 dBmV

2                              Locked                  ATDMA                                 5                5120 kSym/s      39.60 MHz          47.50 dBmV

3                              Locked                  ATDMA                                 3                5120 kSym/s      22.80 MHz          49.50 dBmV

4                              Locked                  ATDMA                                 2                5120 kSym/s      29.20 MHz          47.50 dBmV

5                              Locked                  ATDMA                                 1                5120 kSym/s      35.60 MHz          47.00 dBmV

Expert

 • 

105.7K Messages

That's a bit better ! Upstream channel #1 is still high. Around 45dB is the sweet spot.

Here's the desired specs from the sticky troubleshooting tips post at the top of this board;

 

Specification      Min             Max
Downstream Power Level    
Cable Modems -10dBmV +10dBmV
Gateways and EMTAs -7dBmV +7dBmV
Downstream Signal to Noise Ratio 35dB -
Upstream Power Level +35dBmV +50dBmV
Upstream Signal to Noise Ratio 31dB -
Upstream Receive Power -2dBmV +2dBmV

 

Bottom line. Is the problem gone now ?

(edited)

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

 • 

6 Messages

EG, thanks for the post, and reference to the sticky (forgot to check there first)...   It was.... for ~7 hours, then it's periodically been rebooting where the levels seem in line with a couple channels bordering on the threshold of the high end.  One of the instances found itself in the perpetual power cycle where I just did a hard reset and like magic it was back up with channels locked in with good levels.  I'm really starting to lean on the modem being flakey

Official Employee

 • 

2.5K Messages

Hello and thank you for coming to our Xfinity Forums! Our fantastic expert has given you some great advice with your concerns. However, you mentioned some time outs and I would love to check the signal here on our end to determine if there may be an underlying issue. We truly appreciate your business and I want to make sure no stone has been left unturned. Please send us a private message with your name and service address to Xfinity Support by clicking the chat icon at the top right of the page.

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

Expert

 • 

105.7K Messages

3 years ago

@user_88852d 

Looks like more work needs to be done. Good luck with it !

forum icon

New to the Community?

Start Here