album art refresh

[unfilter]

my music collection is pretty spotty when it comes to album art. so i've started using picard to retag the files with embedded cover art. i typically use the web interface to stream subsonic at work, and try as i might, i can't get the new cover art to be used. same with isub on the iphone. i've tried rescanning the media, as well as cleaning up the database. this is on a windows install, in case there's a cache i need to delete or something. any suggestions?