Several times a day my ability to upload is interrupted (calls or games are paused) while my download appears to be fine. I've looked into my modem's logs and found occurances of "Dynamic Range Window violation" when these interruptions occur. Below is a snippet of the log:
Tue Feb 23 10:33:30 2021 Critical (3) Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=********;CMTS-MAC=********;CM-QOS=1.1;CM-VER=3.0;
Tue Feb 23 10:33:31 2021 Warning (5) Dynamic Range Window violation
Tue Feb 23 10:57:29 2021 Critical (3) Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=********;CMTS-MAC=********;CM-QOS=1.1;CM-VER=3.0;
Tue Feb 23 10:57:30 2021 Warning (5) Dynamic Range Window violation
I've also investigated the modem status and found that the Upstream Bonded Channel power level dips below the "Recommended Min US Power Level" of 45dBmV around the time these violations occur. I see levels as low as 43.7 dBmV.
Is this enough information to troubleshoot my connection issues? What are your suggestions? Power cycling my modem does not fix this issue.
That's not what that message means. The upstream power level is fine !
Arris is wrong ! They have been passing the buck and have been conning people with that statement lately !! They are probably trying to cover up for their liabilities about the lawsuits against them because of their use of the horrible Puma 6 chipsets... Only the Comcast plant / engineering specs matter;
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
Something else is going on.
Please post a screenshot or C+P all of the text of the signal status padge. Include the downstream channel stats. And post the error log entries in their entirety.
The above log are the only entries made today. Below is a screenshot of the status around the time of the second error. (I've tried several times to upload a png to this response and all I see is a yellow triangle. Hopefully you're able to see it.
In case it doesn't show, here's a link to the file: https://forums.xfinity.com/t5/media/gallerypage/image-id/50788iC1FCE8A24EDE823D )
Can't see your pic. Since you are a new poster, it needs to be approved by a Forum Admin. That could take some time. In the interim, you could try hosting it at one of those free third-party pic hosting sites like Imgur or Photobucket and post the link to it here.
Or as stated, copy all of the text of the status page and paste it into the body of your next post here.
Status The statuses listed show the connection state of the cable modem. They are used by your service provider to evaluate the operation of the cable modem. Startup Procedure Procedure Status Comment Acquire Downstream Channel Locked Connectivity State OK Operational Boot State OK Operational Configuration File OK Security Enabled BPI+ DOCSIS Network Access Enabled Allowed Downstream Bonded Channels Channel Lock Status Modulation Channel ID Frequency Power SNR Corrected Uncorrectables 1 Locked QAM256 9 471000000 Hz 3.6 dBmV 35.9 dB 23261 16077 2 Locked QAM256 1 423000000 Hz 2.9 dBmV 36.1 dB 29179 15400 3 Locked QAM256 2 429000000 Hz 3.0 dBmV 36.1 dB 30653 15541 4 Locked QAM256 3 435000000 Hz 3.2 dBmV 36.0 dB 28440 14842 5 Locked QAM256 4 441000000 Hz 3.1 dBmV 36.0 dB 28830 15727 6 Locked QAM256 5 447000000 Hz 3.4 dBmV 36.0 dB 26109 15517 7 Locked QAM256 6 453000000 Hz 3.5 dBmV 36.0 dB 25764 15478 8 Locked QAM256 7 459000000 Hz 3.6 dBmV 36.0 dB 25354 16573 9 Locked QAM256 8 465000000 Hz 3.8 dBmV 36.0 dB 25291 16446 10 Locked QAM256 10 477000000 Hz 3.8 dBmV 35.9 dB 23790 17178 11 Locked QAM256 11 483000000 Hz 3.7 dBmV 35.8 dB 22753 17600 12 Locked QAM256 12 489000000 Hz 3.6 dBmV 35.7 dB 22091 16692 13 Locked QAM256 13 495000000 Hz 3.6 dBmV 35.7 dB 24008 17005 14 Locked QAM256 14 507000000 Hz 4.3 dBmV 35.3 dB 23298 18188 15 Locked QAM256 15 513000000 Hz 4.3 dBmV 35.6 dB 22171 18333 16 Locked QAM256 16 519000000 Hz 4.4 dBmV 35.5 dB 24249 17659 Upstream Bonded Channels Channel Lock Status US Channel Type Channel ID Symbol Rate Frequency Power 1 Locked ATDMA 3 5120 Ksym/sec 29200000 Hz 45.5 dBmV 2 Locked ATDMA 1 5120 Ksym/sec 16400000 Hz 47.4 dBmV 3 Locked ATDMA 2 5120 Ksym/sec 22800000 Hz 45.7 dBmV 4 Locked ATDMA 4 5120 Ksym/sec 35600000 Hz 44.0 dBmV Current System Time: Tue Feb 23 10:57:55 2021
O/k even though the signal stats looked o/k at that snapshot in time, the error log entries may indicate that something is going on. Perhaps there is noise ingress into the line(s) / an upstream channel-return path impairment somewhere.
There are other signal stat figures that can't be read by the modem. They are the "Upstream Rx Power" (Upstream Receive Power Level), the "Upstream SNR Ch." (Upstream Signal To Noise Ratio), and the "Upstream ICFR" (In Channel Frequency Response). These are as equally important in diagnosing connectivity issues as are the modem's stats.
I'm going to escalate your issue to the Comcast corporate employees that are available to these boards. They can check the CMTS (Cable Modem Termination System) for any real time degradation and / or error reports, see your node / cable plant and modem health, and see whether or not everything is in the green zone. They can also see a history plot for the modem and poll for those upstream receive signal stats.
You should get a reply here in your topic. Good luck !
Welcome to our Xfinity forums, @ReluctantOne! Thank you so much for taking time to reach out about your internet connectivity issues. Please send me a Private Message with your name and address so I can take a closer look at the signal levels.
To send a private message, click my name " ComcastEmilyS", then click "send a message".