rhythmbox restarts after exit

Binary package hint: rhythmbox

I first filed this as a question, as I am only able to reproduce it on one of my two Ubuntu systems. I am using version 0.11.5-0ubuntu2.

When I exit Rhythmbox, it restarts itself (or something else restarts it) immediately, with a new process id. It does respond to SIGTERM however, and does not respawn itself after being terminated. pstree shows it as a child process of init, which doesn't tell me much.

I can reproduce this behavior regardless of how I start Rhythmbox. It still restarts itself at exit if I start it from the GNOME Applications menu, or simply running "rhythmbox" from a terminal. The new process is not attached to the old controlling terminal in the latter case.

I can reproduce this behavior regardless of how I exit Rhythmbox. It still restarts itself if I exit by selecting Music -> Quit from the menu bar, close the main window, or select Quit from the notification area icon.

It does not appear to be in my GNOME session at all. When it is running, it appears in gnome-session-properties as style "Normal", and if I remove it, it simply starts itself again.

I am using a fully updated Hardy beta system. I cannot reproduce this problem at all on my other Hardy system. This problem first appeared a couple of weeks ago; I had already upgraded from Gutsy and I'd used Rhythmbox a great deal before this issue appeared.