Quick update - went ahead and rented a Panoramic modem. It's using different downstream channels which aren't throwing uncorrectables anymore. However, the upstream channels are the same, and I get an identical amount of packet loss (2% over about 5 minutes, with large spikes to 20-30% periodically). I still have internet hangs where streams, downloads, websites, and meetings completely halt for about 10 seconds a few times an hour. My family in the area uses Cox with 0% packet loss, and my cellphone's internet also has 0% packet loss.
I will go ahead and contact support - I think I can say for certain that there is an issue on their end. While my downstream uncorrectables seem to be okay now, that seems to be only because I'm on different downstream channels. My upstream channels, being basically the same, likely still have an issue that is leading to the packet loss. Either way, there's an issue somewhere to be fixed.
Mostly just wanted to post this update if anyone else is troubleshooting out there, and to make a more concise story for when I include this thread when contacting tech support.
