Not sure if this is related but I am going to post a response for similar problems that might help other folks. When my Airplay came through with no sound, I went to Settings, General, then Restart (at the very bottom). Then waited a few seconds for the tv to reset itself. Airplay streamed with sound after that.
Today, I got that display you mentioned "Untitled, Unknown Artist, Unknown Album." All my panels disappeared, the screen was totally dark except for that "Untitled..." message which just kept flipping back and forth. The tv seemed stuck in a loop, unresponsive to the remote control. The solution to this is to unplug the power cord to your apple box for 3-5 seconds then plug it back in. You should then see the apple icon reappear on your tv as it resets itself and all your panels (apps) should return.