Both totem and totem-pl-parser had been previously installed, uelsk8s. But I did try something else that at least got rhythmbox partly operational - I installed a bunch of gnome files (ones that I guessed could be connected - gnome-applets, gnome-common, gnome-desktop, gnome-do, gnome-do-plugins, gnome-media, gnome-menus, gnome-menus-xfce, gnome-panel). Following the installation of these files, rhythmbox would start up, although it gave plugin errors for cover art and jamendo, which it still couldn't load. It plays my music and radio, but there seems to be a long delay when music is switched until it starts playing. I downloaded Banshee and noticed the same thing.
There seems to be something universal about Amarok - it always works as it should in any distro. Plays all music with no delays in VL; I just prefer rhythmbox.
One other question. Having loaded all those gnome files, I expected to have the option to actually run gnome, but that option wasn't present in the startup panel.