I purchased a 555 in November. This past week I had the camera around my neck. As I entered a door, the camera swung into the door. It was a very light hit. The camera was powered up when this happened. I took a few more pictures, then turned the camera off. When I tried to use it again it would not power up. I discovered the automatic lense cover was not covering the lens. When it banged the door, it broke. The camera senses this condition and will not power up in picture taking mode but will power up in playback only. I think this is a very weak spot with this camera. If this is typical, this camera will be no good for hiking, riding a motorcyle or any other activity where a slight jar might occur. Anyone else have any comments?