Are you using X68 only in your topology? Or you have any other decos in it?

X86 only. Also noticed NO devices are using the 5GHZ band and internet speeds are diminished. Tested my speed with a direct wired connection to the modem and received 350-400 mbps vs 75-150 wired through the X68. Probably gonna nuke and pave tomorrow and see if that helps...

Weird, seems like firmware malfunctioning. You can either do by 1) Hard reset the decos through the pinhole at bottom for all the X68's and try set it back up again. 2)Rollback/downgrade firmware to a previous version and see if its still there.

are you using WPA3? or WPA2? In certain cases, one of my friend had devices slow down or total entire disconnection in the house and most devices will fail to even connect despite the router is working fine. At first initially he suspected it was a defective device, but later on found out it was actually the WPA3 being the culprit, he changed back to WPA2, and is still running fine as we speak today.