Sorry guys...thought I had caught this issue on camera several times. The weirdest thing happened. The camera was fully charged, though I had it plugged in to a receptacle as it could sit there recording for hours. After the main turned off I reviewed the footage on my computer. The camera recorded 2 separate movies, like someone stopped and started again the recording. If I pause the video the second before power goes down, the camera seems like it was shaking, though it was really the screen becoming distorted. Then the next clip shows a dark room with me walking into it to turn back on the breaker.
Now I took the camera and plugged it into the wall and filmed myself reciting a speech, mid way through I pulled the cord out of the camera and the video never skipped a beat. I figured there would be an issue going from AC power to battery with the camera but my test proved that false. I'm leaning toward an issue of a bleed off from neutral to ground. I can't explain my theory just yet, but I am convinced it is some kind of neutral issue.
I now have a small 1KW generator I plug the camera into, so hopefully I can catch this phenomenon by using an external power source.
So you weren't in the room when the breaker got shut off, correct? And, you could see some camera image movement just before the camera misses a few seconds of image, just coincidentally the few seconds that transpired when the breaker shut down.
I think this is something physical. My biggest hunch is some human is doing this and they are pretty good at fooling you. (I am a Penn and Teller fan).
Next would be some kind of vibration or shifting of the building structure. But vibrations don't turn cameras back on.
AND, this is the part that intrigues me the most, and I think is the best clue for the source of your problem. In your own words, "The camera recorded 2 separate movies, like someone stopped and started again the recording".
I will bet if you asked your camera tech he would say the same thing the breaker techs are telling you. That can't happen. If I were Penn or Teller, I would hone in on 'like someone stopped and started again the recording', which is probably exactly what happened.
How about doing the video again, only this time lock the breaker on, or lock the panel door. If that isn't possible, there is this stuff called 'Dykem Steel Blue'. It's a layout fluid for metal workers. It's a cobalt blue dye that doesn't dry on metal or plastic but makes an almost permanent stain on skin. Lightly and evenly coat the breaker handle with dye. If a human so much as touches it, they will get blue on their fingers. Even if they manage to hide that from you, close inspection of the handle will reveal smudges, or maybe even fingerprints, if it has been touched at all.
Back to the video. You say you have 2 separate movies. Check the 'properties' of the movies and you should see the exact date and time each one occupies, right to the second. Look close at when the first one stopped and when the second one started. How much time elapsed? A second or two, or enough time for a person to shut the main down and turn the camera back on?
Thanks for keeping us in the loop. Pay no heed to those that offer no other alternative than to blame the spirit world. This is an interesting problem and I assure you the cause is not supernatural. Also, it stopped being humorous quite a while ago. I am sure you are at your wit's end over this and I hope you don't stop posting because of people poking fun at you.