I've been using this amp (bought from ebay ) via the optical inputs for a while and have been having no problems. I've bought a new PC with 6ch outputs, no problem I thought,just a case of plugging it into my Technics amp and away we go. Sadly it was misbehaving and it made no sense, center + sub responded randomly and the rear inputs didn't seem to work. Brainwave time, checked all of the inputs on my hi-fi amp (Technics C1000m2, family owned from new, NOT from egay!) and they all work perfectly, as does the sub when plugged directly into the computer. So is it new amp time or is it worth getting the DX950 repaired? I bought it because it matched the rest of my system (ST-GT550 + SL-PS6700) and all looked rather nice (if you like old technics stuff!) but now it is pretty much useless to me. I have just bought a quad core media PC so need/want the surround sound. What do I do?