This problem could be caused by an animation threading lock bug that was fixed in Clearlooks cairo a few days ago. I've backported this fix to Ubuntulooks as well, so it's possible that this bug is now fixed.
-- Crash when changing songs https://launchpad.net/bugs/57040 -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs