There is a 10amp fuse behind the radio - you could check that, but it sounds like your radio is bad. I believe (but may be wrong) if that 10 amp blows you wouldn't get any sound at all. You could, however, check the wiring and make sure all the speakers are working - but I doubt that would go at the same time - which leads back to the HU. With that said, eBay & other sources (chech classifieds in here) have the HU for pretty reasonable prices. Hope this helps...