I have 4 HD210s (3.5.77) running 1920x1080p@29.97 mp4 videos with the screen resolution set to 1920x1080p@29.97. The videos are short 1-4min but there is an obvious flickering white/black line at the bottom of the screen.

Any ideas for a fix?

Is it possible the screen doesn't support that resolution?

You can try updating firmware to the latest 3.7.x.

You can test other content, like some of our sample videos.

You can also test another refresh rate for 1080 to see if there's a difference.

It's either a firmware issue (but it's not one I've seen before), a content issue, or a monitor problem with the selected resolution and frame rate.