Channels/DVR/Guide freezing and locking up anywhere from 10 seconds to minutes.

Whenever I try to change a channel from the guide, or access a recorded show, or use a DVR function on live tv, my tv just freezes. I can't do anything but power off... But when i push power on, it's still there.  If I push multiple commands while it's locked up and frozen, it executes all the commands upon resuming activity.  This seems to have started in the last 10 days or so, and it appears there was some type of update.  Anyone know what's going on?