Something I noticed that could be better (though doesn't do any serious harm):

I created a soup based on play_count, so that I could see which tunes I overplay (and to stress-test your code ). I have set play_count to have java.lang.Integer as its typeClass and sortClass, like so:

jempeg.tag.play_count.sortClass=java.lang.Integer
jempeg.tag.play_count.typeClass=java.lang.Integer

But the soup view isn't sorted in numerical order, as the attached image shows. How difficult would it be to make the soup views sort using the same class as the corresponding column? I'll give you a hint: the answer we want to hear is "not very"