This was a problem I was having that I recently solved and wanting to share the solution I discovered online so to make a more recent post making it's easier to find :)
On an HDMI input, my splash screen video would cut out half way and the screen would go black until ES started up.
Press F4 going to command prompt
type sudo nano /opt/retropie/supplementary/splashscreen/asplashscreen.sh
find "omxplayer -b--layer 10000 "$line"
and change it so it reads "omxplayer --layer 10000 "$line"
basically eliminating the "-b"
press Ctrl+X to save
press Y to save
and Enter to leave
then you can sudo reboot and voila!
I figure most users have a handle on editing command line stuff but this is for those of us who are no so savvy
Hope this helps some of you!