Just wondering if you ever resolved this? I am having the same problem and I am wondering if I have a open Pre-Amp where a Loop Bar is supposed to be? I had once upon a time a Bose Amp plugged in. Now I do not longer need it I wonder if I need to place those loops back in. Sort of like closing a circuit if you will.
Presently, I only have my rear speakers working. With the Bose Amp that I had plugged in a long time ago, it controlled the front and center, which does not work now. I am thinking my replacing the bar loops it will allow the front and center speakers to work.
I recently acquired an old Pioneer VSX 9700s A/V reciever from an old friend. It seems to work fine, switching on and seeming to ouput sound by way of equalizer bars. However, it does not ouput any sound at all. Although speakers are hooked up, there is not sound emitted and nothing happens at all. What could the problem be, and could I possibly fix it myself? Any input is appreciated.

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