I have a refined Fly Deluxe from around 2005, and the output is hissy. There is static white noise coming out regardless of any vol / tone setting. It is audible in high-gain settings, not with a clean amp. The level is a tad stronger than a normal passive pickup, say a Duncan 59, but the problem is that while with normal passive wiring the noise goes down as you turn the volume down, with the parker the hiss stays the same and makes the vol pot useless in any other than max setting.
First of all, is this normal? Is the Fishman Powerchip preamp supposed to be dead silent? Should I just buy a new one and replace it?
Second, I don't really need the possibility to mix piezo and magnetic pickups. Would it be easy / possible to wire the system in a way that I would have direct magnetic or piezo-only setting so that the preamp would be bypassed completely for the magnetic pickups using the standard components there? I have basic understanding of the electronics and soldering, but the powerchip makes everything difficult.
EDIT: Is it the second wiring diagram in the Wiring diagrams in this forum

EDIT2: Well, I just followed the diagrams and at least the magnetics are now passive and the piezo should be on the other stereo channel. I don't have a proper cable to test it out. Could it be modified to mono so that the magnetic vs piezo could be selected with the switch without having the blend option inbetween?