Playlist folders not shuffling evenly

[random1destiny]

I have a playlist folder with playlists from different singers. However, when I shuffle this folder one playlist/singer completely dominates my queue. And it seems to be whichever playlist is at the bottom of the folder. In the picture you can see 75% of the songs come from the Nina Simone playlist. 

There is clearly some shuffling but for some reason it is massively overweighting the bottom playlist. 

All I want is an even shuffle between playlists in a folder. I have like 40 singer playlists making it very difficult to manually combine