Odd problems...

In a couple of videos I've been managing recently, I've found that at a couple random times, the camera seems to shut off and restart. That is, I didn't notice any problems with the camera, either during filming or during transfer, but on playback there'll be a couple of seconds missing, as an instant cut to what happens after those missing couple of seconds. This is concerning; have other videos suffered from this problem? Now I'll have to rewatch stuff to see if it's ok