NOTE: The quality and speed of the sd card is absolutely crucial.
To be able to ensure that the camera will not freeze the SD-card must have a minimum rating of U3.
If it is too slow or faulty the camera cannot transfer the data and freezes.
To see a list of recommended SD-card see this article.
To re-boot the camera in case of it "freezing" please follow below instructions:
1. Turn the selector ring to "Power".
2. Hold down the activation switch for 10 seconds, this will reset the camera.
3. Hold the activation switch for 4 seconds, the camera will turn back on.
If the problem persist please see this article