Thanks for the comment! Just to clarify, I'm not experiencing lag, but a total disconnect from the internet, evidenced by the physical status light on the ISP-p

Thanks for the comment! Just to clarify, I'm not experiencing lag, but a total disconnect from the internet, evidenced by the physical status light on the ISP-provided modem itself. I once had a similarly flaky issue about 20 years ago that was exactly like yours: after 3 months of back-and-forth and chewing my way up the chain with a regional ISP, they FINALLY did what they should've done to begin with: check the damn line. And once they did they figured out the problem: copper oxidization. The building's cable lines had been installed something like 30 years prior (which would've been back in the 70's!) and had become badly oxidized over time, even out in the desert where I lived at the time!