Bose Lifestyle home theater

Hello all, Im a regular on the projection thread but now i have a problem that fits here. I have a Bose Lifestyle system that is about ten years old. It still has an incredible sound and works perfectly 90% of the time.   THE PROBLEM: Every now and then The different channels cut out on me. Usually the left channel goes first, Then the center channel. The subwoofer is of course the center hub for all the components so my current fix is to simply smack my hand atop the subwoofer encasment. this will usually bring all the channels back. It seems like a short in the system but im geussing its inside. If anyone has any experience with this issue please please help me! We do ocassionally entertain friends and its a little embaressing when the sat. radio sounds so good and then just cuts out. thnx again! Techlore has been great to me thus far so my hopes are high on this one!:)