Trevor Donjeany

Hi Can anyone assist ? I purchased the Marcus miller V7 whilst on tour in the US 2 years ago. My batteries dont last a week ! I read that there are other players who have experienced the same problem. It seems that some of the basses are wired incorrectly , as the batteries should last a year , or more ,if the jack is unplugged when not in use . I would really appreciate some help , or a schematic so i can get it wired properly . Regards Trevor Donjeany