I have an Eden Metro which I love, but when I run direct (from back of amp) to the board for larger gigs, I get alot of buzzing noise. I run a box in between my bas and the amp, but then my sound is at the mercy of the mix. What is wrong with my amp? I also notice noise at my house even at low volumes, and it stops when I touch the strings. (Ground) This doesn't happen when playing live. The only issues are when I go direct. Help.