Hi Giles

> 1. The modules all seem to have a 60hz hum on output. It's low level,
> but it's there. I haven't done much trouble shooting yet, Just tried a
> different outlet. The fact that it's all modules that I tried, (2
> mixers and a filter), makes me thing there might be a power supply
> issue. Is there a way to confirm this with a basic multimeter

does the hum also appear if you don't connect the A100 to any other
equipment (no audio connection, no midi connction) and the connect a
headphone to the output of the audiomodules

Florian