So, I thought I had it all figured out.
The sound board makes a lot of distorted/garbled noise.
The PO told me it was a voltage regulator. I replaced both VR1 and VR2 on the soundboard.
I also found VR1 on the power supply damaged, so I replaced that as well.
I tested the voltages coming to the soundboard and they seemed OK compared to what I've read around the forums: +12= +11.2vdc +5= +5.1vdc -12= -14 vdc.
The AC ripple I'm getting on the +12v side is around 300mv or so. Not ideal, but I didn't think that would be causing this.
I've been mulling it over and I'm wondering if it's possible all 3 output amps could be blown.
Here's a video of the audio in diagnostics
.
You can hear the "sounds" underneath all the s*** somewhat.
Any ideas? I'm about to pull the board out again and hit with my ESR to see what I can see