Well I figured out my remote pairing problem this morning. I run Cisco Meraki wireless AP's in my home (I work in IT). I could not pair a remote to my Roku Ultra, thought I had a bad one, returned it, and had the same problem again. Turns out that Cisco Air Marshall was detecting the Roku direct wifi network (created by the Ultra, that the remote connects too) as a "rouge" access point, and was putting it into containment, not allowing anything to connect to it! That is a security feature for business networks that the Meraki gear supports on the 3rd radio. I whitelisted the Roku "DIRECT-roku-011-DD77BA" network and now remotes are pairing and everything is working fine!