I've been having multiple disconnects of my fairly new (15 months) old Netgear CM500-100NAS modem. The issue started 3 weeks back and I've had numerous calls with Xfinity Support without any resolution, The case is also escalated to Advanced Support and Field Technician came in to check levels of signals and installed an Amplifier but that hasn't helped. I showed the on-site technician the modem logs which he didn't know how to interpret.
I've tried by-passing the Amplifier and the intermittent disconnects still persists. Looking at the previous threads apparently someone with username - @ComcastChe was able to magically resolve these issues remotely.
The Xfinity App shows my Internet status as "Red". A reboot of the modem fixes the issues sometimes until it tries to re-initializes the registration and the logs are flooded with the T3/T4 time out issues.
Below is the screencapture of Modem Event log when things are working, The uncorrectable errors go up in 4-5 digits. I've replaced all the Coax to the modem and also the splitter was replaced by Amplifier so everything coming in the house seems Ok - Layer 1 wise.
I've also seen the Upstream and Downstream LED go to amber once in a while.