When I amplify my double bass my open D string is much louder than any other note. This doesn't happen when I'm mic'ed or playing acoustically. So far I've tried equalization by cutting the lows, and muting the instrument by placing a rolled up towel between the top and the tail piece. Both of these have only helped marginally. Does anyone have any other advice or know what else might be the cause of this? I realize that I might not get this perfectly evened out, but where it is it absolutely kills my control over the dynamics of the instrument. Oh and I'm using a Shen SB80 bass (low end, I know, but it's what I could afford when I was in school), a Fishman full circle pickup with bridge adjusters, and playing through either an Ampeg B2-R with a 1x15 Cab, or various Behringer combos in rehearsal spaces.