you may feel comfortable doing this, may not, but its a suggestion:
Unscrew the amp plate from the back, and on it you will see two daughter boards. These are for the left and right channels. On each of them there is a fuse, in all likelyhood one of the amps either has several burnt out components, which would be obvious by looking at it, or the fuse is blown, which you can just pop out and look at to tell. If you get a new one and it keeps blowing it, just send it back, klipsch offers repair services on all of their systems, to fix anything that is wrong with them. It is also very reasonably priced :D.
pioneer 3 ways now fully functional (need new crossovers though), kole 740w car amp (using first 2 channels, 185wX2) and (drum roll) a TV as a preamp!! (at least now its a 61" projection HDTV)
But really, i have promedia 2.1's, with 16ga cables and gold plated ends, and they rock.