Screensaver video bias

[yamanobe96]

I have emulationstation set up and in use on a windows pc.
I have added 10 game hardware titles and 400 game software titles each, registered the game titles, image.png and movie.mp4 in the gamelist.xml file, and all titles are displayed without any problems.
The screen saver is played when the game is not being played, but there is clearly a bias in the movies played.
After 2 hours of playback, about 240 titles are played, but why are the same videos played so often when there are nearly 4000 games registered?
Can you at least prevent the same title from being played during one cycle when the screen saver is running?