If am near my computer, I can get all kinds of awful noise, no matter what my guitar is plugged into. It gets much worse depending on the angle between the computer and the pickups. I wasn't sure what on the computer was causing it, but it may be my gpu fan, as well. I wonder if there is anything I could buy/make to stand on the floor, between the computer and me, to block out the interference.
If you can replace the fan - that would be ideal. On Macs it's non trivial - one of the downsides of everything getting smaller. With regards to shielding it - it's unlikely. You might be able to slightly improve it - but really shielding it would be a lot more trouble than it's worth I would guess. I looked at that possibility - but there's no real good way to do that. I figured I couldn't be the only person out there experiencing this. I can tell you it's soooooooooo nice to have the amp quiet now. Now maybe I can actually learn how to use it.