panasonic sa-ht75. region fault?

every disc i put in is being read,it knows it is surround,5.1 etc but then flashes up on screen that its an incorrect region while putting in the correct region and even region free discs so it wont play anything at the moment!
no idea how it changed but i had downloaded a movie,burnt it to disc then tried to play it.could this have disabled it? help!!!!!