Currently playing song not shown when playing through Connect

[tjugan]

Every so often when I'm playing music from my desktop computer (Mac) using the desktop app, the app stops showing the currently playing song in the playlist that is marked as playing (highlighting and making the icon change next to the song). The playlist itself in the list view to the left hand side of the application shows what playlist is playing (the volume icon thingy next to the name), but when selecting that playlist, no song is green.