Forum Discussion

blwilson87's avatar
blwilson87
New Contributor II
2 years ago

Not receiving DOCSIS 3.1

Up until last week my ARRIS SB8200 was receiving DOCSIS 3.1, indicated by the blue lights on the front of the modem. Directly wired in I was pulling 900-940 mbps down. Those lights are now lit green, representing DOCSIS 3.0, and I’m now limited to 500-550 mbps. I’ve tried numerous resets and even bought a second SB8200 to test, same issue  

I have had no changes to the coax line and I am not using a splitter. Looking for suggestions, hoping to avoid the $75 charge to have someone out to my home if at all possible. 

DOCSIS 3.0
DOCSIS 3.1
modem
slow download speed

12 Replies

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  • Darkatt's avatar
    Darkatt
    Valued Contributor III
    2 years ago

    If you are only connecting 3.0, and not 3.1, it's indicative of either noise on the ofdm channel, like WMO suggested, or bad levels. Try replacing any splitters and barrel connections, and the cable cord from the modem to the barrel connecter. 

    • blwilson87's avatar
      blwilson87
      New Contributor II
      2 years ago

      Right now, the coaxial is running 50 ft from the wall, directly to the modem. Currently no splitters or barrels between. I can definitely try a new coaxial and could change out the wall plate. I posted my signal levels, but not entirely sure what I am looking at there.

      • WiderMouthOpen's avatar
        WiderMouthOpen
        Esteemed Contributor
        2 years ago

        Right now your signal levels are really bad. You are not locking half your channels, and the OFDM has no SNR lock. Also you upstream is too high. Should be below 50dB. Can you connect direct to the wall (minus the 50') and post what your signal levels are then?

  • WiderMouthOpen's avatar
    WiderMouthOpen
    Esteemed Contributor
    2 years ago
    hoping to avoid the $75 charge to have someone out to my home if at all possible. 

    BTW, the charge is only if the issue is inside the home. If you have tried a new modem and have a direct connection from the demarc. then there is very low chance that the issue is chargeable. 

      • Becky's avatar
        Becky
        Moderator
        2 years ago
        Hi Blwilson87, I agree with WiderMouthOpen in regards to your signal levels and channel bonding. If you aren't able to improve your metrics, a service call may be needed. I want to increase your speeds so you can enjoy your internet! Please email us at cox.help@cox.com if we can be of further assistance. -Becky, Cox Support Forums Moderator