I just realized it was pretty late when I called.
Post here or email me back what you find after changing the battery. If the distortion you heard is the same in both pickups, that's the likely cause.
If after you change the battery you find the distorted sound is only in one pickup, then the problem will probably be in one of the filters.
I will check my email again in about an hour. Tomorrow I've got an appointment from 11:00-12:00, but I'll be here the rest of the day. If you call in earlier, ask for Ron, my dad.