I couldn’t figure out why my ATV2 was in a Lowtide (the menu) reboot loop. I did the beigelist remove, re-add trick (http://forum.firecore.com/topic/7837?page=2#comment-39252) but that didn’t seem to fix it. I couldn’t figure out what was going on (1-2 hrs of troubleshooting). I then remembered a topic thread (http://forum.firecore.com/topic/7837) I’d read about people using Unblock-US. I just joined the VPN this past week. I have their 3 DNS IP’s in my router so all my home traffic goes through their DNSs. I went to their website in Chrome and lo and behold, it indicated while my DNS entries were fine, it flashed me that ISP had changed my address. One click later and my IP was updated in their records, and when I walked back to my ATV2 the Lowtide reboot had stopped.
TL;DR - If you’re using a VPN like Unblock-US (awesome BTW)…if your ATV2 acts silly, check your VPN connection before anything else.