My husband's iPhone 6 has a weird "problem". Recently, the phone started flashing a picture when he unlocked it. It was a quick flash & he was only able to get a glimpse of what appeared to be a woman in a red dress. It wasn't any of his pictures & he can't reproduce it on demand. Just now, the picture flashed long enough that he recognized it is an album cover from one of his albums. So, that mystery is solved but we can't figure out why the phone flashes that picture at random times when he unlocks the phone. Anyone else experienced this?