The play-out of a media stream by a play-out device may be synchronized by a synchronization subsystem with a reference play-out, thereby obtaining a degree of synchronicity with the reference play-out. To address a structural deficiency in the obtaining of the synchronicity with the reference play-out, the play-out device may report a quality of sync metric to a metric subsystem, which may then be analysed to identify the structural deficiency. A corrective action may then be scheduled to address the structural deficiency. Examples of corrective actions include re-clustering of play-out devices, adjusting priority and/or bandwidth in the streaming, etc. As such, the quality of experience of one or more users experiencing the play-out may be improved.