Intermittent Packet Loss on irregular basis

The past few years, my household occasionally had intermittent, irregular packet loss. We had techs come out and check signals, cables and splitters. Upon using applications like PingPlotter to see where the loss was happening, it was always the routing through Xfinity servers. The problems randomly lessened over time, but it seems to have returned again within the past month, and when I ran PingPlotter to see where it was happening, lo and behold, Xfinity servers were the issue. Here's a screenshot of what a simple ping test to Google looks like on the network:

25% packet loss is average during these times (and it has spiked at over 50% in the past), during which nobody in the house can realistically take work calls, play games, or even use the internet in general.

We had this issue even when we were using the Xfinity modem/router combo, and the internet was actually better once I swapped it out with my own modem/router combo. This issue is ridiculous and the fact it's returning after a year or two is driving me to the point I may have to seek other alternatives for internet soon if there isn't a way to resolve it.