[Bug 49483] Re: rhythmbox close button should minimise to tray

[Rich Johnson]

interesting. if you uses the Music menu in Rhytmbox and select close, it
does exactly what you want, but when you click the 'X' it quits.

http://www.ubuntuforums.org/showthread.php?t=156358
this link is pretty much the same exact thing you just asked too. I just found it searching the forums.

A quick fix is to "Music > Close" in the menu list, or you can simply
press: Ctrl+W to close it to the system tray. If you see anything else
or find out anything else please post it, maybe somebody will come by
with a fix to this.

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rhythmbox close button should minimise to tray
https://launchpad.net/bugs/49483