I have a Sony DD/DTS receiver STR-DE835. I bought it in '99 and it's a damn good piece of equipment but the volume knob has begun to stick when I'm using the remote, not all the time but enough to bother the crap out of me. I have to get up, hit mute, and jiggle the volume knob back and forth until it will work again. I'm sure the problem is the knob and not my remote control, which is in perfect working order with fresh batteries. So, how much will this set me back to have repaired?