In Ubuntu 11,04, while Banshee is open and playing music, if you click on the exit button in the title bar, banshee continues to play music, but in the sound menu (that part is normal I guess). Then, if you try to "unmaximize" any window by dragging its title bar (the panel) toward the center of the screen, you will notice that you just can't drag the window anymore without pressing the maximize button. This bug doesn't happen if you minimize banshee rather than close it.
Binary package hint: unity
In Ubuntu 11,04, while Banshee is open and playing music, if you click on the exit button in the title bar, banshee continues to play music, but in the sound menu (that part is normal I guess). Then, if you try to "unmaximize" any window by dragging its title bar (the panel) toward the center of the screen, you will notice that you just can't drag the window anymore without pressing the maximize button. This bug doesn't happen if you minimize banshee rather than close it.