I know its not a pedal issue but when i am building my pedals i like to run some music from my laptop through my small amp but the thing is it's so noisy, like i can hear the static glitchy noises that comes from the laptop, is there something i can buy or even make that will filter the audio?
is there any point that is connected to an actual ground in your set up?
i have used the same technique with the same problem, but i'd use clean guitar instead of music, and the solution to my problem was a ground cable clipped to my radiator.
cheers, Iain