Matsui freeview box?

I've had this box for about 2 years and i have it running through an amp that i also have the dvd player, video player and Wii running through. The freeview box has been working fine until the other night. I went into the kitchen and when i came back it had no sound. I know it's not the amp cos everything else running through it has sound. I've twiddled wires at the back and done everything i can think of, any ideas or should i just buy a new one?