Test it by hooking it up to another output on the back if there is one. If not, hook up an Ipod using a 1/8 phono to RCA adapter and see if you get any sound that way.
don't have any of those unfortunately...how do i test if theres a signal going to the sub enclosure? or from the audio out jacks? Then i could determine if the problem's with the audio out or the speaker wiring.