I put in my third set of brand new lithium ion batteries at $20.00 a pop. In a week it totally drains bank 2 I get anything from 0 to .2 volts. But bank 2 voltage remains exactly as they were to begin with, 1.5v. Unit functions properly. My experience with electronics tell me this is impossible, and am wondering if there is electronics which allow switching of bank 1 without losing data is the causing the issue.