Rapid battery drain

[Chappers]

At the worst time possible, my active bass (Yamaha BB615) seems to be draining the battery extremely quickly.
While playing for 5 - 10 mins, the volume dropped quite a bit. I changed the battery, and within 20 mins, the same thing happened again.
Has anyone any experience of this happening?
Are there any checks I can do on the electrics?
And is it possible to play without a battery in, without wrecking anything?
(I've an audition for a band on Wednesday and I NEED my guitar working!!!)
Any help appreciated,
Col

[The Burpster]

Should it not work as a passive even with a flat battery? I cant find enough info on it from Yamaha to answer this but your manual shoudl tell you this...

If so, plug it into the passive input on your amp rather than the active input and turn both pup volumes up to max and then back them off as req'd.

[Soulfinger]

I had that problem once - turned out to be a broken solder joint inside the battery clip.

I´m pretty sure the BB615 doesn´t work in passive mode.