markus_h_photography
Established
I'd suggest that it's a problem with the electrical current from the batteries.
As the OP states, everything works fine in manual mode, it's only in Auto that the problem arises. The fact that the mirror will sometimes release when tapping the bottom plate would indicate to me there may be a slightly corroded wire in there somewhere.
Unless you're really emotionally attached to that particular camera, I'd just leave and use it in manual mode as the cost of getting something like that fixed would probably run into several times what the camera's actually worth.
As the OP states, everything works fine in manual mode, it's only in Auto that the problem arises. The fact that the mirror will sometimes release when tapping the bottom plate would indicate to me there may be a slightly corroded wire in there somewhere.
Unless you're really emotionally attached to that particular camera, I'd just leave and use it in manual mode as the cost of getting something like that fixed would probably run into several times what the camera's actually worth.
