I have over 1500 albums in my iTunes library, and most of them have cover art. The iTunes screen saver is great, but sometimes it gets itself into a mode where there is a very small subset of the cover art that appears on the screen saver. It is always the same small selection of 30-40 albums. I have no idea what they have in common. In the past I have been able to work around this by overwriting the iTunes folder with a back-up copy., but then the problem just seems to come back again (I suspect it does so every time I add new music, but I haven't been able to prove this). Any ideas what's to blame?...