I have a markbass combo amp that I have been using for my upright and it's pretty good but sometimes it is too muddy even with the bass rolled all the way off. The D and G string usually sounds fine but the E just sounds like low frequency noise sometimes. If I turn the highs up I get to much finger noise (if that makes any sense). I was wondering if anyone else had any experience with this and of so if they figured out how to get a more even/natural sound from a mark bass amp. And just for reference I have a Khor plywood bass and I'm using a rev solo pickup.