So I just got a TX-SR705 yesterday and hooked it up only to find out that it's outputting extremely low volumes on the center channel. At first I thought it wasn't outputting anything at all until I tried raising the center speaker volume as well as the entire system volume to max and then could just barely hear anything coming out of the speaker. I tested the speaker elsewhere and it was fine, as was the wire, which leads me to think that the center channel amp is bad. Is there anything I could try before exchanging this unit?