A very quilted-figure Mitchell acoustic in for a dead pickup.  The first thing I always check with acoustic pickup issues is the battery.  As the voltage drops, so does the headroom of the onboard preamp eventually fading away to silence.  This happened to be missing a battery all together so a fresh 9V brought the pickup back to life.  The player was surprised that it was just the battery as he had tried replacing it himself.  I've had other pickup fixes in the shop solved by a new battery so maybe I just get lucky sometimes.