Need to pick some brains.

I have 3x U7 Pro XG APs in my house. Everything has been perfect ever since install, which was shortly after these APs were released. Nothing has changed since, except on Jan 27, it updated to firmware 8.4.6. That’s when things started to go upside down, when ONE of the three APs started giving me an extreme amount of trouble, and I’m not sure if it’s something I should RMA or maybe a setting somewhere. 

Essentially, this AP just completely randomly and without warning slows all traffic to a crawl. Nearly everything in “WiFi Experience” goes to poor. There doesn’t seem to be any rhyme or reason to it. Rebooting the AP SOMETIMES helps. Other times I have to reboot everything (all APs, UDMSE, USW-Pro-48 PoE) multiple times for it to get ahold of itself and return to normal. 

It could be perfect for days, or weeks. Or even just hours before it goes bad again. 

Everything was manual before. I set channels, RSSI, etc. no issues according to AirView. Even when the problem is ongoing, everything is all good according to the console. I decided to move everything to auto, and also ran UI’s WiFi Doctor and Channel AI. It made very few changes and didn’t improve the situation. 

I’m kind of at a loss here. Any help would be appreciated. 

U7 Pro XG Issue