I've got a friend's Alvarez guitar. It recently stopped outputting any sound out of the output jack, so I told her I'd take a look at it.
Sure enough, brought it home and the preamp/controls light up and seems to be functioning as it should, but there's no output.
Yes, the battery is fresh.
I have another cheapy soundhole pickup and the Alvarez preamp happens to have a 1/8" aux in jack, so I unplugged the transducer from its input and plugged in the soundhole pickup into the aux in and *voila* sound.
So, my assumption is that the undersaddle transducer just up and died (?) which I guess could happen, but why?