Digibox lost signal. . . ?

Hi! was watching free view and all of a sudden the signal was lost. have tried all the usual leads etc, leaving it for 1/2 an hour etc. but to no avail. the tv in the other room (no digibox) has also lost the picture, like there is no ariel. have checked ariel, looks ok, somebody got any ideas! thanks
Answer
Ours got stuck & none of the buttons worked. phoned the bloke ufacturer and , even though it was past its guarantee, they sent a new power supply free of charge! now it works like a dream.