This is caused by a known gstreamer bug, http://bugzilla.gnome.org/show_bug.cgi?id=340492. The "flacdec" element doesn't support push-based operation, and the "gnomevfssrc" element doesn't support pull-based operation, so it doesn't work.
-- playback error when playing flac files from remote shared library https://launchpad.net/bugs/35725 -- desktop-bugs mailing list desktop-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/desktop-bugs
