Short solution : delete a bundle of albums . When browsing through my albums I noticed Coverflow did not show all artwork, just a bit and then a lot of empty covers with a music note in it. Rotating back to normal view and going back to Coverflow again showed the artwork of the currently selected album and albums in that area, but not the artwork of albums at the beginning or the end of my collection. Then I thougt : there's not enough memory to show all artwork. And I was right (like always ). I deleted a big amount of albums, just to see if it was memory related, and now Coverflow always shows all artwork.