On my windows 7 computer, I get the notification "huidige nummer kan niet worden afgespeeld" which means "current song cannot be played" occasionally. When I get the notification, the song seems to play if you just look at Spotify, but there is no sound. I then go to another song and it plays, and then back to the original song. So far it happened three times the last month, two of which were the last couple of days. So far it only happens when I want to play an album (I mostly listen to albums on Spotify) and only on the first song of the album.