Very odd problem - DirecTV DVR

For Very odd problem, relating to DirecTV DVRs and receivers. I'm having a strange problem and I'm curious if anyone else has had a similar experience. My bedroom receiver, an older standard Hughes box, loses the local Fox channel around the same time most evenings. Sometime between 8:30-10:30 EST, it goes dark, showing "Regular Schedule" as the program and a "Searching for Signal" message. If you look at the signal strength when it is on Fox, it is 0. All other channels are unaffected and show normal signal strength.

DTV was of little help, suggesting the usual reboot (did not work - it actually caused all local channels to disappear for a short time). Fox eventually comes back, usually before too long, but it's pretty frustrating when you're trying to watch something. The Tivo box in the living room does not experience the same thing, even at the same time it is happening in the bedroom.

Is this familiar to anybody?