White line appearing at the top of recorded videos

[CRYPTIC]

Hey guys,

So I have attached the original image of the lightbulb I'm using for a visual effect. As far as I can tell, there's nothing up with the original; no lines, it's in 1920x1080. The project itself is also in 1920x1080. When I record, however, the rendered file has a white line on top. Any idea what's going on?

Also, what's even weirder is that when I screenshot the recorded still video with the line on top, the screenshot doesn't show it, but it's definitely there while playing the video.

Thanks for your help! If it helps, I can send the 6 second video to anyone that might know the problem, it just won't let me attach it here.

[Zoltán]

Spotting a line on the edge of a video is pretty hard in a player, the window pixels will be there too.
If you make the clip smaller with transform, does the white line move?
If it does, it's likely encoded in the video.

It's in the screenshot you uploaded btw