Battery drains on fishman piezo chip even when unplugged

[Emory]

I have an Ovation VXT (2 SD 59's and Fishman undersaddle with chip), stereo output. For some reason unknown to me, the battery seems to be draining even when no TRS stereo cable plugged in. I have been using a bit of credit card to break the battery connection after playing (when I remember to, anyway). Guitar works fine, seems no apparent short that might cause such a situation...

You guys are much wiser than I, and wonder if you could give me some tips/ideas to check out. Can't take it to Ovation service as I live in Thailand... hmmm

[DeepEnd]

You might simply have a bad battery. If a new battery doesn't do the trick you might try replacing the jack. Looking at the guitar, it doesn't look like it would be a difficult fix.

[Idunno]

If the cable jack contacts close (touch) when the cable is removed you'll have a drain. I recommend pulling the cable out and attempt to inspect the jack to see if the contacts are touching, or perhaps FOD (foreign object debris) is shorting the contacts. You might even have a bad battery box, or battery terminal clip. Obviously the drain is small (milliamps) or things would heat up noticeably local to the drain. If you own or have access to an ohmmeter remove the battery and place your test leads, one probe in each of two contacts, in the battery clip. The reading should be into the 200 megohm range (millions of ohms) or higher, meaning the path is essentially open (non-conducting) with the cable removed. Anything less will be considered a short that must be isolated. I'd start with the jack. If you can't perform any of the forgoing and can't really see the jack, get a small wood dowel the same diameter as the cable and place it in the jack as you would normally plug in the cable. Then check to see if the battery has drained in the time you've noted it was draining before.