I created a Spotify playlist. Some of the songs I have in my music library some I put in from Spotify. Five tracks (of over 90) won't play. I deleted them from the playlist and added them again via Spotify itself. Still not joy. Those songs will play on Sonos via Spotify or via my music library - just not in the playlist. These are hardly obscure (Born to Run, Get Up Stand Up). How do I fix tis?