I had this problem also, after installing libgio-cil it started up fine.
It appears to be a dependency problem.
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banshee crashes on startup
https://bugs.launchpad.net/bugs/632495
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I had this problem as well. Though from my experience is that it is on the
panel.
It's more a case of the icon which should be showing, isn't loading up. So you
are left with an invisible area of a couple of pixels wide which I could click.
(Only noticeable by a slightly bigger gap than between
