Implement in the server session messages (X created the session, Y joined the sesson, Z left the session, ...) and playback messages (X pressed play, Y pressed paused, Z added N tracks, Y removed N tracks, W changed the order of tracks, ...) and handle them in the client.
Implement in the server session messages (X created the session, Y joined the sesson, Z left the session, ...) and playback messages (X pressed play, Y pressed paused, Z added N tracks, Y removed N tracks, W changed the order of tracks, ...) and handle them in the client.