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Intermittent Connectivity Issues

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Intermittent Connectivity Issues

We switched from Comcast Business to Xfinity about a month ago and for the last week our internet has been dropping multiple times a day, most of the time a reboot is required to recover. For reference, we have an MB8600 connected to a Eero Pro and there are splitters from the pole (one filter and two couplers). Our WiFi network is up and locallty functional when the internet is down.


We've had multiple visits from Xfinity and every time the "signal looks good". One phone tech admitted they could see signal issues around the time of our disconnects. Another phone tech "resolved" our issue, it sounded like he boosted the signal but I wasn't able to get a straight answer from him on what he did and he simply "promised" our internet was fixed after "monitoring it for 3 hours".


It appears every time the internet drops we are seeing T3 timeouts from the modem logs:

  Time  Priority  Description 
   Time Not Established Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=<redacted>;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;
   Time Not Established Critical (3) No Ranging Response received - T3 time-out;CM-MAC=<redacted>;CMTS-MAC=<redacted>;CM-QOS=1.1;CM-VER=3.1;


Connection Status (after rebooting modem):

Downstream Bonded Channels




   ChannelLock StatusModulationChannel IDFreq. (MHz)Pwr (dBmV)SNR (dB)CorrectedUncorrected
   32LockedOFDM PLC48655.0-1.637.731378380

   Upstream Bonded Channels




   ChannelLock StatusChannel TypeChannel IDSymb. Rate (Ksym/sec)Freq. (MHz)Pwr (dBmV)

Re: Intermittent Connectivity Issues

The signal stats are in spec. Please post the error log entries in their entirety. Those "Time Not Established" ones are basically unhelpful.

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