White flash in embedded movie

Hello,

I am exporting a 20 second video from AE CC 2014 to be used in Flash Pro CC. I am exporting the video as a .mov (which I then turn into an mp4 with Adobe Media Encoder).

When I import the video into Flash (load external video with playback component), everything works fine, but I get a few WHITE FRAMES (or a white 'flash') at the beginning of the video.

This person seems to have the same problem, but hasn't found a solution:https://forums.adobe.com/thread/1935875

Thanks!