Ack, I really should have updated this but since I solved the problem it wasn't a priority.

Long story short (pun fully intended) there was in fact a short on the output of the right channel. There was a small strand of wire bridging the right rear channel. Now, what's crazy is that I haven't used the rear channels for going on 2 years now and it was only because I tightened the unused binding posts when I installed my new front-channel cables that caused the problem. D'OH! Most importantly I'm now happily enjoying my 1050 again. For a while there I saw a 970/7075 in my near future! I'm hopeful that I found the short before it did any real damage.