No, it's not broken (jumper 3, I assume). I checked it and all the rest of the jumpers) and it was good. I decided to replace it anyway but still no audio from panel unless I plug in the speaker cable.
Additional info: If I do not have the speaker cable hooked up, I hear hum from the panel. When I first turn on the 706, the meter scale is pegged out and I have to slightly rotate the RF gain knob to clear that. Once that clears, if I turn the volume knob, I then hear sound from the 706 transmitter body speaker. The output of the panel still has a hum and other noises coming out of it. Once I plug in the speaker cable, the 706 powers up correctly, no hum, and I have clean audio from the panel and do not get the s-meter pegging out on power up. Hope this helps.
Joe W4WT