have old telecaster nashville with fishman piezo power bridge. someone resoldered pots etc and wires were broken off. so rewired and sodlered all connections. checked pots with ohmmeter and seem ok. hard to tell if piezo board is working or not, but it is wired in. now when plugged in, i get no volume until turned all the way up and then just a little (and switch works to switch pickups, but same low volume). piezo bridge squeals and then nothing from it. tone pot seems to have no effect. any suggestions (can't believe all the pups are bad) - even tho pot seems ok by ohm readings, could it be bad... any thots on piezo deal - overheated or shorting out?