I have this special issue with Spotify on Android:
There is one song (and only that song) that will not play on my Note II when it's added to a playlist (both online and offline). If I delete the song from the playlist and start another song, then I'm able to play the defect song when online (and not in my playlist). The song works perfectly fine on Windows application.
Song: CHVRCHES - Gun
Phone: Samsung Note II