My old router, a Netgear Nighthawk, has had a known bug in its firmware versions for the last several revisions and I was tired of the issues it was causing. So, I recently purchased a brand new Archer AX600 wireless router. The problem I will describe did not happen on the old router, but is present on the new with the latest stock firmware, and with the new beta release from a few months ago as well. If I could, I'd love to find a solution for it. It's not a show-stopper, but it is an annoyance:

I have great serve with everything else, but my smart TV, a 2017 Samsung 65", suddenly has issues with several channels, the worst of which is YouTube of all things. Whereas before, on the old router, the streaming and download of thumbnails was snappy, suddenly there's a huge amount of latency. Just getting to the profile selection can take as much as 10 seconds, and once I log in, I've seen video thumbnails take as long as 20 to 30 seconds to load. I haven't been able to play a single video that didn't take an additional 20-30 seconds to start, then buffer within 10 seconds at least once, if not more often. This is extremely annoying and I can't figure out what the issue is. The odd thing is, this doesn't happen in a browser on my laptop or even over smart phones, which are all linked over wireless, of course..

QoS is turned off in the router and everything else is pretty well set up the same as with the old router. The TV, itself, is connected over Ethernet not over wifi. When I do connect it over wifi as a test, the delay times elongate slightly, as I'm sure everyone can imagine. I have a dummy switch in between the router and the TV, which I have hard-booted several times.

The router shows 731.83Mbps download and 18.96Mbps upload. No clue what could be causing this. Anyone have any idea?