I have had a dozen instances of this problem in the past few months. Motion triggers a recording to be made from a web cam. The icon for the recording is correct. However when the recording is played back it is not the recording that was made at that time, but is a recording that was made previously.
I would not have noticed this except that when the recordings in question are recorded it is daytime but the recording that plays when the icon (which also shows a daytime picture) is double clicked it is of a nighttime recording.