Last night, I set my GH2 up (with the Sanity hack) to shoot a play. On previous projects, I was able to simply set the camera up, and let it run. Sometimes I'd have to change the battery at intermission.

However, last night, during intermission, I found that the battery had run out before I could stop the camera manually. I replaced the battery for the second half of the show. At the end, I found that the camera had switched off on its own, despite having power and memory to spare.

Today, I find that some of the video files are missing from the card. They're numbered 00000, 00001, 00003, 00004, and 00006. Can't find 00002 or 00005 anywhere.

Now, this hasn't happened to me before. My first suspicion is that the battery running out caused the loss of 00002, since 00003 begins after the intermission. Can't understand why 00005 vanished, 00006 just ends abruptly.

Are there any explanations for this, and ways to prevent it from happening again?