It turns out that it's rhythmbox's fault. gstreamer grew a richer URI format for cdda:// URI's, and rhythmbox has been using a different format for a long time, which has happened to work, because gstreamer ignored the extra data in there.
It turns out that it's rhythmbox's fault. gstreamer grew a richer URI format for cdda:// URI's, and rhythmbox has been using a different format for a long time, which has happened to work, because gstreamer ignored the extra data in there.