There's no audio regardless of whether the attenuation's turned on or off, there's just a buzz and background noise.
He's tried other games with the SG and they all work fine with no audio issues.
The SG's one I built about a year ago and used myself since. I've ran a bunch of different stuff on it with no issues, even Cave stuff which I've read can be troublesome with attenuation. I've never however tried either of those 2 boards.
We've checked the following:
+5v & 12v at the JAMMA edge and
ruled that out.
Played both games in 2 cabs - they've no audio issues.
Adjusted the volume pot up on the board with no effect.
...but no joy in diagnosing the problem

Before we arrange a return for diagnosis has anyone experienced any similar issues with these boards whether it be with a supergun or cab, or does anyone have any suggestions?
Apologies in advance if this would be better placed in the supergun section and thanks in advance for any help
