The left channel of of my Denon receiver DRA335R intermittently has no sound. I have identified the problem is the relay DH2TU, which connects to the speaker terminals. If I knock on it, I could make it work for a while and then no sound again. The right channel work normal all the time. I wonder if I need to replace the relay, or I can open it up the fix it or some other parts turn off the left channel of the relay. Which vendor sells this kind of relay? Thanks keffan