Hey Guys, I just bought these pickups and got them wired in with the existing EMG preamp that came stock in the bass. It worked for a little while and then I started getting this annoying popping sound. So I checked around and rewired the preamp only to find that now I get no output. Took it to the local repair shop and the guy said that the EMG40hz have a "preamp" installed in the back of the PUs which is why the Basslines won't work. Is this right? I did as much research as I could before I bought these to make sure they would be compatible with the system I already have. I need anything you guys have on this!!! Thanks!