Does all passive bass guitars hum and have ground problems due to the lack of a active pre? I wastold that most passive bass guitars hum especially with the pickups rolled to one side. Is this true? If not can someone post a diagram on how to properly wire a passive bass. The knobs are vol, blend, and passive tone control. I get bad hum when I'm far away from the amp and some of the hum goes away if I touch the strings or bridge or cable for that matter. Help me Please! I hate this hummm with a passion.