followers only see a small piece of my public playlists

[coxmartex]

I'm a fairly new premium user and have made 40 or so of my playlists public.  My friends who have tried to listen to them can only listen to a fraction -- say 7 or 8 out of 20 -- songs from these lists.  The playlists were originally transferred in from iTunes, but I have gone back and made sure each song was a spotify version, and replaced the ones that weren't.  What's up