Starting today, I have been unable to add new music files to iTunes. I thought it was something isolated to one new album, but trying to add existing music (copied with different metadata) also fails. The files are playable in the Finder and QuickTime and the permissions are correct, permissions have also been repaired using disk utility. No messages appear in the log when attempting to add files, they simply do not get added, no warning or error dialog, nothing. Can anyone give any ideas as to why this is happening?