In the last week, streams on several apps on our TCL Roku TV have stopped to buffer.
The TV has a wired connection with a CAT8 cable that is less than a month old, to a gigabit router and we have a 400MB/s minimum connection from our ISP. Both the modem and the router are fairly new, both capable of gigabit speeds. We have unplugged and rebooted the TV, router, and modem. None of these issues have resolved the problem. While streaming, I have monitored the speed on the router admin panel. After a stop to buffer, the download speed drops to 0, then picks up to 1.2-1.3 MB/s, before the stream continues and then it hovers at around 0.3MB/s until about one second after the stream stops to buffer and then afterward the download speed on the router drops.
Internet speed tests show perfect connections on multiple devices.
Edit for further into: unplugged wired connection to TV and connected wirelessly via 5Ghz to modem mounded to the back of the TV and had similar connectivity issues. Played the same stream via iPhone connected via HDMI to TV and watched the entire show in 4K without a problem.
apps tested: Netflix, Prime Video, Apple TV.