I have a very small hum, it's not that audible but it's there and if I crank up the volume it's there and very annoying. The funny part is this: if I put any flesh part of myself on the cord going from the guitar to the audio interface or touch the audio interface with my foot the hum goes away.
Right now I'm playing with one foot on the metal casing of the audio interface but I'm pretty sure I don't have to do that, but I don't really understand what the hum is coming from or how to get rid of it...
Okay, after some digging around I figured out what it was, and it had to do with the wiring inside my acoustic guitar. As soon as I touch any of these parts inside the guitar this hum goes away but while fiddling around inside the guitar I managed to do something at least, temporarily. Because the hum went away and I played for a couple of minutes but then it came back.
I've ruled out noise from other source there's definitely something going on with the pickup so If anyone with some expertise on the subject cares to weigh in, I'm all ears.
It's an Guild acoustic guitar with steel strings using a Fishman acoustic guitar pickup.