After a couple years of puzzling i just solved my "eats batteries" problem. I had determined by symptom analysis that the guitar did not shut itself off when unplugged. I found that the connection for the middle ring on the jack would touch the body of the guitar when the jack was properly mounted on the body. The cavity is painted with black conductive paint. When the middle connection touches the paint it is always connected to ground and the guitar never turns off. I insulated the connection and now i don't have to take the battery out after i play.