Comcast Xfinity cable through a Linksys CM100 modem. . .
Consistency of Service varies from 30%-75%
I connected my PC directly to the cable modem and confirmed the consistency of service is still problematic.
So I called Comcast tech support. They were NOT helpful. In fact I don't think they are knowledgeable at all, they seem to just read off a script e.g. the rep didn't know the difference between a switch, hub and router. The only thing they could tell me is that my cable modem is outdated (DOCSIS 2.0) and I need to upgrade (DOCSIS 3.0. The could not explain why it would make any difference for VOIP.
So I upgraded to a Zoom 5431J cable modem. UL/DL speed has increased a little (1-2 Mbps) and consistency of service has improved a little (mostly yellow light, 50%-70%). Calls still occasionally get choppy. Longer term testing will see if this has solved the problem.
Has anybody with Comcast cable experienced high levels of consistency of service (~90%-100%)?