Switch in off position, install battery, camera powers up.

There have been a few reports about the same issue. It can be something as simple as a contact problem with the ON/OFF switch to as complicated as a shortened SMD resistor. It is also possible that your camera may my have a write function error. This could lock up the when the buffer got full and wont clear after that. When you pull the battery and then reinsert it, you manually clear the buffer. So as you can see, there are a variety of possibilities. Here is a decent site explaining a bit about the SMD part. the other thing I would try and do,is a firmware update, for that check on here. The complete Service manual including parts list and schematic is available right here. Hope this will get you going in the right direction. Good Luck