Currently media-sound/rhythmbox doesn't depend on media-plugins/gst-plugins-cdparanoia. If media-plugins/gst-plugins-cdparanoia isn't installed in the system, rhythmbox can't play audio CD and fails with an "unable to access device" error. gst-plugins-cdparanoia should be a mandatory dependency or at least should be controlled by an use-flag.
Will take care of this soon. Looking at fixing another bug today before adding a -r1 to the tree.
fixed in cvs with 0.9.7-r1, thanks for the report.
I just want to mention that I and probably some others too prefer gst-plugins-cdio for playing audio cds because cdparanoia and gst-plugins-cdparanoia just do not work for me with a pata cdrom controlled by libata (gentoo-sources-2.6.19-r4).