I just went to play an old DVR recording and discovered that ~300GB of recordings are just *gone*. Why would my DVR delete that much without asking me???

I can't figure out how to use any of the buttons at the top of the screen when I'm watching a program. And when I go the 'MISC' button and click on any of the little buttons that come up on the bottom, I usually get trapped on a menu that I can't control or get out of without restarting the...