I recently upgraded my AC-5300's to wifi 6 by getting the RT-AX55's. I did this mainly because i'm having a weird throughput issue. I thought that maybe it was an issue between compatibility of my GT-AX11000 and AC nodes but i'm noticing that still with the RT-AX55's wifi speeds are cut in like half and it randomly happens. All my nodes are ethernet wired and ethernet connected devices are getting full 1gig speeds from my ISP. My wifi devices right next to the router connected to 5ghz channels are getting like 200mbps / then if I reboot them or play with any setting it goes back up to 600. I notice that this random drop just happens every so often even setting the channels to specific ones doesn't fix the problem. I can't seem to figure out why this is happening. I'm thinking it's some kind of bug with AiMesh. Nothing changes in my configuration but then all of a sudden I connect to the wifi router and the device is right next to the router getting abysmal speeds. I noticed this also with the AC-5300 that if I used ethernet backhaul and connected to 5GHz-2 the speed was abysmal if I connected to 5GHz-1 then speeds are in the 600's. The issue is my RT-AX55's are now picking channels 149-165 instead of the lower range channels 36-64. I notice that clients that connect to the lower range 5ghz channels don't have this issue. That is consistent on both the RT-AX55's or the AC-5300's.