Hi All, I installed Bart pickups, and a Bart Preamp (NTMB) in my bass. I however am getting a hum when I turn my bass all the way up, and gets worse of course when I boost the treble. My first question is whether this is normal for bart preamps or do I have a ground issue. If I do, how can I get rid of it. Second question. What is the easiest way to ground the preamp to the the bridge? Do I have to cut through the wood? Is there a neater way?? Do I have to ground it to the bridge or can I ground it another way? Any electrician experts out there who can give me some advice, please let me know.