I have a MusicMan Sabre that I've never had a problem with the battery. I might have to replace it twice a year no matter what position the knobs are in or if it's plugged in or not. Now, I have two other active basses that the battery dies real fast like days or weeks. If I unplug the bass and turn all the knobs down will that kill the drain? 9 volts cost a ton. Thanks.