How does Apple TV select album/poster art for menus?

This question has been bugging me forever and I've never even seen mention of it anywhere.

When I select Music in the menus, my Apple TV always cycles through album artists starting with the letter "Z". So every time I pause on "Music" I see Frank Zappa mostly cycling on the left of the screen. These aren't even the last albums alphabetically in my iTunes and Zappa not the last artist either. But it happens every single time without fail....the same Zappa album art. Weird.

But even weirder is when I go to the "Movies" menu. It cycles on movie posters for Charlie Chaplin, Buster Keaton, and a selection of movies that all seem to have in common that they feature Denzel Washington. Again, this happens every time I hit this menu, even after updates and reboots.

So my question is, what is the algorithm or the parameters the Apple TV uses to set this cycling art in the ATV menus? I'd like to see some variety.

Colin Law