Why can't I tune in my alba DV3?

Why can't I tune in my alba DV3? I Bought one for my daughter and it started playing up by switching on and off all on its own then it started dropping channels and eventually would not tune in to anything.
She had a brand new one last christmas (2006) but it was the same make and model again. Guess what this one has mirrored the problems of the original.
I have since installed a different make in her room which is working perfectly.