I have the same problem, but it only shows a little of my friend's activities. I have like 30 friends and can only see 5... really frustrating. I have a friend that is right now listening to several musics and I can't see him on the feed.
12-05-2018 still not fixed. Tried everything, including uninstalling and installing. I've got friends that, according to spotify, haven't been active for a week or more and yet they are listening to music right beside me.