For a month or so now, the Channels app is locked up just about every time I turn on the TV. If we left a program playing but paused, the program will finish but then the app won't respond. Have to exit out to the AppleTV menu, close the Channels app, and then restart it fresh.
We tend to leave Channels on our AppleTV running 100% of the time; the only thing we turn on or off is the television. I assume that either something in Channels or the AppleTV has timed out or gone to sleep, and it doesn't recover gracefully.
I would say this started happening about the same time they released the updated UI (with e.g. a different layout for the TV Shows screen), but I'm not sure.