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mgids's avatar
mgids
New Contributor
5 years ago

Intermittent Disconnections (Dynamic Range Window Violation)

For the past several months I've been having intermittent disconnections throughout the day. This is really noticeable while working from home, since my RDP connections will stall for several seconds whenever it happens.

Digging around in the modems logs, I noticed that whenever these disconnections occur, the modem records the following warning events:

  11:51:56
Sun Oct 18 2020
  Warning (5)   RNG-RSP CCAP Commanded Power Exceeds Value Corresponding to the Top of the DRW;CM-MAC=00:40:36:5f:d0:ba;CMTS-MAC=00:42:5a:1c:90:f0;CM-QOS=1.1;CM-VER=3.1;
    11:51:56
Sun Oct 18 2020
  Warning (5)   Dynamic Range Window violation
    12:11:55
Sun Oct 18 2020
  Warning (5)   RNG-RSP CCAP Commanded Power in Excess of 6 dB Below the Value Corresponding to the Top of the DRW;CM-MAC=00:40:36:5f:d0:ba;CMTS-MAC=00:42:5a:1c:90:f0;CM-QOS=1.1;CM-VER=3.1;
    12:11:55
Sun Oct 18 2020
  Warning (5)   Dynamic Range Window violation

Other users on this forum have reported similar issues which are likely due to a problem with the signals being sent by Cox to the modem. The error at least, suggests that the Upstream command signal coming from Cox is higher than it should be.

I tried a support chat and it was completely useless. The "tech" rebooted my modem and said it would fix it without providing any context to my logs. Unsurprisingly, this did nothing.

Any chance I can get in touch with a Data Tech who actually knows what this error means? I'm certain this is fixable, but no amount of modem reboots and wire tightening is going to help.

  • Dave9's avatar
    Dave9
    Contributor III

    This message indicates that the CCAP (i.e., the equipment at Cox your modem connects to) requested a power level on one channel that's significantly higher than on the other channels. But it didn't just do that for no reason. Most likely, it did that due to a spike of noise on the upstream frequencies. These noise spikes are almost always caused by something outside of your property and outside of your control. It's impossible for you to identify the source on your own. Your only hope is to call and speak to a support technician who will hopefully schedule a tech visit, or when a Cox employee posts in this thread you can follow their instructions for e-mail support. The tech will need to be able to see the problem happening in order to troubleshoot it. It might take multiple visits to correct the problem. Don't use chat support for this. The chat support technicians are not sufficiently trained to understand this type of issue.