A stop button would be a highly useful addition to the interface, since at the 
moment there's really no way for me as a simple user to tell the application 
that I want to stop what it is doing. It makes me jealous that the application 
itself will stop when it reaches the end of a playlist, but I cannot duplicate 
that. This is problematic because my normal behavior is select a different 
artist and/or album after reaching the end of the playlist and then hit play, 
which works fine. On the other hand, I am continuously confused when I try to 
duplicate the stop functionality (by hitting pause, for lack of a better 
option), select a different artist and/or album, then hit play and of course 
unpause the current track instead of playing the new track. It seems like 
pretty simple functionality to be able to tell the application "I want to stop 
what you are doing" so that later or immediately the playlist state can be 
changed and then the application can be easily told "Please, start playing 
again" without forcing the user to double click on a track name. 

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