I have a high amount of uncorrectable and correctable (T3 and T4) errors. The modem has only been powered on for 1 days 01h:17m:34s.00, according to my Cable Modem's uptime statistic. The coax cable going into my modem looks a bit warped at the end. The coax cable running downstairs may be a bit old. This house was built in 2002. Is this concerning, and is there anything I can do about this?
There are errors in the event log, like "Dynamic Range Window violation", but I didn't want to post the log publicly, because there are things like MAC addresses in it.
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My uncorrectable/correctable errors persist. I am also seeing issues of high power on my modem.
A tech came out to help me with my internet service (very friendly). He tracked down my downstream problems to the wiring inside the house. We were able to wire a new coaxial RG-6 cable from the modem to the basement drop. Although this seemed to fix my downstream speed issues, uncorrectable and correctable errors persist in my modem.
I've tried to reach out to people on this forum before twice about these same issues, but nobody was able to respond and help me with it. Can someone from corporate please help me with this/test it? I see no end in sight and I'm really getting tired of having all this packet loss/errors making me already stressful working from home life worse.
Power seems a bit high on channel 25 and 129. Note that 129 seems to always be the first to go ahead and spit errors.
Image: Cable modem WebUi errors. https://imgur.com/a/7c7g054
I am now having '"MDD message timeout;CM-MAC=xx:xx:xx:xx:xx:xx;CMTS-MAC=xx:xx:xx:xx:xx:xx;CM-QOS=1.1;CM-VER=3.1;"', "Dynamic Range Window violation" errors, and "RNG-RSP CCAP Commanded Power Exceeds Value Corresponding to the Top of the DRW;CM-MAC=xx:xx:xx:xx:xx:xx;CMTS-MAC=xx:xx:xx:xx:xx:xx;CM-QOS=1.1;CM-VER=3.1;" errors.
Tech that came out didn't stop these errors it seems.
Also "SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=xx:xx:xx:xx:xx:xx;CMTS-MAC=xx:xx:xx:xx:xx:xx;CM-QOS=1.1;CM-VER=3.1;", and
"No Maintenance Broadcasts for Ranging opportunities received - T2 time-out;CM-MAC=xx:xx:xx:xx:xx:xx;CMTS-MAC=xx:xx:xx:xx:xx:xx;CM-QOS=1.1;CM-VER=3.1;" errors.
These issues just seem to continue to get worse.
All of last week, while I was trying to work from home, my download speeds kept dropping significantly. When I mean significantly, I mean to 0.60 Mbps-40 Mbps, even at 1AM. After a week of that, we called 1-800-COMCAST to send a technician out to try and fix our service. He told me that the problem was a cable running through my home, and that he saw downstream fluxuation with the cable that went through our house, and not the cable that ran from my coax amplifier outside to my basement.
I am also having frequent internet disconnections, almost every few hours.
Long story short, we ended up replacing that cable with the guy's help. He said that after that cable was replaced, my service should remain stable, and he even showed me his monitor with the seemingly stable numbers. I remained suspicious though, since he orginally said he only saw the downstream fluxuations after around 15min of monitoring. It seemed to work fine for a few days, although I still noticed very high uncorrectable/correctable errors, although the speed seemed to be fine. Here's my modem's downstream channels after the tech came https://imgur.com/a/IpaOMcn.
The speed remained fine until today, when the speed randomly dropped to 34 Mbps/40 Mbps upload, even though I had done nothing.
The SMB levels and power levels look very out of whack to me. I have posted the current ones below, about 5-10min after my huge speed drop.
Can I please talk to someone that can ACTUALLY help with this problem. I've called the number 8 times this month, and they keep saying their diagnostic test looks fine among a bunch of other excuses. I even had one guy think I was talking about TV channels when I mentioned DOCSIS downstream channels. I've also contacted support over Twitter, who ran the diagnostic modem test and told me my service was fine.
My internet crashed twice within the last hour, and they line up with when the sync, MDD, RNG-TSP, and T4 errors happened in my log.
Log is attached.
Topic now being closed.