Three times now I have left the battery on my camera and when I go to use it the battery is dead. I must admit, the first time I left the camera on, however the other two times I did not. I know how to stop it from happening (take battery off when not it use LOL), I am curious as to what might be causing it. Has anyone else experienced this? I have the fan set to auto, does it come on even if the camera is set to off?