Video flashing black at end of playback⁠›››

Hey guys, I've had this issue for as long as I could remember, where after playing a video, the monitor will flash black after playback is complete. It seemed like it was just limited to .mp4 file types, so I countered the issue by using .wmv files. They worked great, and still seem to, except a new video I'm implementing today is also doing the flashing, and it's a .wmv. Not sure why it's happening. Any ideas?

Are you showing the video (overlay) on a secondary monitor or on your main monitor? Does it make a difference?

Nick Thissen wrote:
Are you showing the video (overlay) on a secondary monitor or on your main monitor? Does it make a difference?

I am showing the video on my main monitor. The flashing happens only on the monitor with ATVO running. It's just a quick blink. Can't seem to diagnose why it's happening with some videos, and not others.