My music goes back and forth from iTunes to Rhythmbox via Dropbox. All of my songs have their artwork showing in iTunes but some don't when I'm back in Ubuntu. I don't know how to set the artwork in Rhythmbox and setting the file's icon doesn't really do anything. If it's of any importance, the songs that don't have their album artwork show in Ubuntu also don't have it show in Windows Explorer's tile view. How do I fix this?