Originally Posted by
Tannin
It sounds very much like a hardware fault to me. Hope not! But the batteries hold charge when outside the camera, there are three of them all the same, and they deliver something like full performance when in actual use - so I'm thinking something that is triggering the drain. A small short, or a sticking switch that is keeping some function (such as the AF, for example) active. Does the camera seem to go to sleep after the usual period of inactivity? That might give a hint.