Since a few days, Spotify permanently stops playing when the next song should start when listening to one of the Mixtapes.
Additionally I have to say that I am not very impressed by Spotify - so many bugs. The worse is that Spotify permanently fails to play the advertising spots. The only way to recover Spotify is to shut down the program and restart it. My internet connection is not limited at all (DSL Deutsche Telekom), rock stable, no proxy no ad-filter (on Windows or on the net) nothing unusual but Spotify even fails in such a standard environment.
Another error that occurs frequently is that songs start without sound. I have to click on the time-line so the player skips a few seconds (e.g. skip back to second 1) and then the sound is directly there.
I simply understand how Spotify thinks someone would pay money for such a badly working program.