|reply to dorkino |
Re: (Un)correctable codeword count high
Thanks. I'll try getting that info.
I've also tried moving the modem to a different drop, but the T3 errors keep occuring, and the uncorrectable/correctable codewords keep increasing periodically. The upstream power level remains around 44dBmV.
There are not any splitters on the way to the modem either. Only a barrel connector that Comcast installed in the outside demarc box on the side of the house. It's a connector that has a ground wire attached to it. Other than that, it's a straight run from the outside box to a bedroom wall jack, which adds one more connector, then to the modem via a roughly 6 foot cable. Previously, I had this thing hooked up through a different jack in the master bedroom; it was spliced onto that wire coming from the outside to a 50ft wire going thru the attic that terminates in the laundry room where I have all my wiring run. I've since moved it to this other bedroom in an effort to simplify things in the hopes that I can clear this up myself.
Edit: Since I've moved it, the problem remains. It may even be worse, because the modem rebooted from a T4 timeout just a little while ago.
I found a thread on Comcast's forums started by Nerdburg a couple of months ago that indicates suspicion of a possible problem with the 184.108.40.206 firmware and this SB 6121 modem. Supposedly the Zoom 5341J behaves well on Comcast's network, so I'm going to try one of those out. Although, can a firmware issue be to blame for the errored codeword bursts? Isn't that more likely some source of noise entering into the network?
Edit #2: I polled the neighborhood on FB, and many other folks are having similar issues. What would be the best way to have the problem investigated considering this is likely not a problem just at my house?
Cable modems do not read the downstream SNR, nor do CMTS read the upstream SNR. They estimate it based upon the current ration of correctable code words to total codewords. If the modem is reporting a good (high) SNR, then the number of bad codewords is not a problem.