Installed rhythmbox and rhythmbox-plugins but there is no org.Rhythmbox in the list of available dbus services. To view the list I use:dbus-send --system            \  --dest=org.freedesktop.DBus \  --type=method_call          \  --print-reply               \  /org/freedesktop/DBus       \  org.freedesktop.DBus.ListNames 
How to register rhythmbox service on system dbus?
d bus;rhythmbox
Rhythmbox needs the MPRIS plugin enabled (use the plugins window to enable the plugin)Modern Rhythmbox versions (2.90.1 and later) exposes a session dbus entry called org.gnome.Rhythmbox3 when Rhythmbox is actually running.  To see this slightly alter your dbus command:dbus-send --session --dest=org.freedesktop.DBus --type=method_call --print-reply /org/freedesktop/DBus org.freedesktop.DBus.ListNamesAlternatively just use the mpris interface as explained in this excellent Q&A.If you use the application d-feet then this clearly displays the objects exposed by the mpris interface: