Come bloody dine with me !

[4F]

Easy to solve.
Borrow the handset, set tv to what you want to watch.
Using sleight of hand remove batteries from handset and replace with a dead set you had concealed previously.
Hand handset back.

Buy a second handset, remove yourself to the hall and randomly turn the television off every 5 - 10 minutes whilst tring to stiffle your laughter as they scratch their heads trying to work out what is wrong with the TV.