Intermittently throughout the year when watching ST channels, my HR20, it just locks up. Today, however, it is maddening. I can watch a channel and if I change to another, especially from a SD to an HD channel (since bronco game is not in HD), either I cannot change any channels, the menu won't go away, no buttons on remote will work, etc. I have rebooted the receiver like 5 times today. Anyone else have any issues like this?