When playing back DSLR media (or even pausing on certain frames), I get these single grey frames over the image, usually just before a cut. It looks like a solid grey color has been placed on top of the footage with opacity reduced to 50%.
I will wait until I watch the exported video to decide if this is a "freak out" worthy issue.
Grey anomolies only appear in Premiere Pro. Also, I noticed they aren't always present. I play my sequence once, and I see 3 or 4 of these grey flashes.... I play it 10 minutes later, and poof they are gone. However, they do return on occasion.
What do you have your playback resolution set to in Premiere? If it's set to 1/2 or lower, your footage will have an "artifact look" to it. Have you tried pausing the footage on a spot where you see the grey bars and does it go away once it's paused?