Early builds could be suspect builds.
One build working ok could rule out ambient radio interference.
If a wired backhaul to the troubled 86U node, have you tried a different cable or wireless backhaul?
OE
Just to clarify.... I'm running the 2nd 86U in Ethernet wired back-haul mode. Never thought the cable could be the issue as the devices that are connected to it run fine wired and do not lose connection. Also, are u suggesting that I change it from wired back-haul to wireless? Thanks for the help and reply btw!