Three days ago, we upgraded from Comcast TV to Comcast Triple Play so now internet and phone are coming via Comcast. Since that upgrade, the modem has rebooted itself four times which causes an outage of both internet and phone for several minutes while the modem comes back up and gets connected again to both Comcast and to the internal router.
After the 2nd reboot, I called Comcast support and was given the usual advice to remove and reattach all cable connections, plug the modem directly into a wall socket (not a power strip) and power cycle the modem. They offered no additional advice.
I don't have a long history yet, but so far it's about 1 reboot/day. Since I anticipate having this service for many, many years and a modem reboot also interrupts phone service and clearly the service is not supposed to do this, I'm trying to figure out what I should do to get this fixed?
Here's pertinent system info:
The Cable modem is rented from Comcast - Arris Model TG862G and, per the technician who installed it, it was upgraded with the most recent firmware at the time of the install.
There is only one splitter between the pole and the modem (installed by Comcast). One tap from the splitter goes for video, the other to the cable modem for data (both internet and voice).
Internet speeds are what I am expecting - 57Mbps down and 11Mbps up.
Downstream Power is between 1.6-2.2 dBmV
Downstream SNR is 36 dB
Upstream Power is 41-43 dBmV
When the modem reboots, I see entries in the Event Log that look like this:
RCS Partial Service;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
No Ranging Response received - T3 time-out;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
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I will obviously continue to monitor the system for future reboots so I've gathered the maximum data I can for troubleshooting. Beyond that, what would you suggest I do to get my system fixed so it doesn't reboot? When should I demand that a technician come out? The technician that did the install seemed fairly knowledgable and took a lot of measurements on my cable and thought it had good metrics at the time of the install.
Are there better brands of voice-capable modems that are less likely to reboot? How would I know if the Comcast supplied modem needs replacing? I actually intend to buy my own modem at some point (to save the rental fee) but figured I would go with the Comcast installed modem initially so that I could hold them responsible for any issues. Once the system was working and stable, I figured I could then get my own modem.