Hi all, I have a 90's Japan factory jazz bass I put some seymour duncan basslines in along with a J Retro 01 Bass Preamp by John East. The tone is great, but I have a problem. As my fingers rub on the pick guard (when slapping) or as my fingers slide across the strings, I hear a static sound, kind of like static electricity. I don't know how else to explain it. Any suggestions would really help. thanks.