Forum Discussion

Hqpham's avatar
Hqpham
New Contributor
7 years ago

Any way to adjust Cable Modem Downstream Power Levels?

My internet connection has been terrible for the past two months. I have had a technician come now and nothing has been resolve. After researching around the web, I believe the issue is due to the power level my cable modem is receiving (see attached). Are the power levels normal? If you're unable to see the picture, the power levels are all between -10 to -23.

Is there any way to adjust the power level?

https://photos.app.goo.gl/6HpaqcmyPwLgoAbp7

  • Rob_H_'s avatar
    Rob_H_
    7 years ago

    Based on your screenshot, the connection between your modem and the Cox CMTS looks like it could be very noisy as suggested by your very low SNRs (i.e. 26.6 dB, 30.6 dB).  Ideally, you want to see those SNRs at 36 dB or higher.  You could start by trying to bypass as many, if any, splitters you have between your modem and the network termination point for Cox at your location and reseat your connections to the network termination point (demarc). 

    After that, if you find little to no change, the next Cox technician should show up with line testing and RF spectrum analyzing equipment to test and isolate the problem. Please be sure to ask for Tier 2 the next time you contact Cox Tech Support and share with them the very low SNRs you are seeing on your downstream channels.  Good luck.

  • Rob_H_'s avatar
    Rob_H_
    Contributor II
    7 years ago

    Based on your screenshot, the connection between your modem and the Cox CMTS looks like it could be very noisy as suggested by your very low SNRs (i.e. 26.6 dB, 30.6 dB).  Ideally, you want to see those SNRs at 36 dB or higher.  You could start by trying to bypass as many, if any, splitters you have between your modem and the network termination point for Cox at your location and reseat your connections to the network termination point (demarc). 

    After that, if you find little to no change, the next Cox technician should show up with line testing and RF spectrum analyzing equipment to test and isolate the problem. Please be sure to ask for Tier 2 the next time you contact Cox Tech Support and share with them the very low SNRs you are seeing on your downstream channels.  Good luck.

  • Becky's avatar
    Becky
    Moderator
    7 years ago
    Hi Hqpham, I ran a quick test signal to your modem, and the resulting metrics are extremely poor. As Rob suggested, bypass (remove) all splitters, amplifiers, and other extraneous coax connections on the line to your modem. If the issues continue, or if there are no splitters on the coax connection to your modem, I suggest we schedule a service call so an on-site can resolve this for you. My team can schedule a service call for you, if you like. Email your full name, address, and a link to this thread to cox.help@cox.com. -Becky, Cox Support Forums Moderator
    • Hqpham's avatar
      Hqpham
      New Contributor
      7 years ago

      Thanks for suggestions. I do not have any splitters or amplifiers. The Coax cable cord goes directly from the wall to my modem. I also recently had a technician come out to try and fix the issue. The tech was on the phone the entire time with a call center in India trying to resolve the issue. After he was unable to fix it, he kept insisting the issue is with my modem and that I should lease a modem from Cox. My current  modem (compatible with Cox) is brand new and I purchased it because my previous modem had the same issue.

      • Becky's avatar
        Becky
        Moderator
        7 years ago
        Hi Hqpham, I suggest another service call. There is definitely something going on with the signal to the modem. We might need to replace the drop to your house. -Becky, Cox Support Forums Moderator