Stingray Sub 5 making nasty bitcrush noise?

[radiophonic]

The guitarist in my band has a Sub 5 for demos and while I'm happy for him not to be able to influence the bass parts too early in the process, I do feel sorry for him. His instrument has started making a noise like a very quiet broken bitcrusher - spitty and gated, no top end at all and really quiet. He did send me a wav but it's embedded in a facebook message and unfortunately I can't download it. It's not the battery. All the wiring is intact and there is nothing visibly wrong with the pre-amp board. He's had it from new and never gigged it, so physical damage is unlikely. He needed to max out the gain on his interface even to record a sound, so the output is very weak. My guess is a cap has gone bad - but it didn't slowly deteriorate, it just started doing it from cold one day. Anyone encountered anything similar and know where to start?

[itu]

I would still check the battery. If you have a DMM, is the voltage present at the preamp? Is the output jack loose? Any wires loose, battery, pickup, ground etc.

Low voltage capacitors are very seldom an issue on a unit like the preamp.