A data processing apparatus includes circuitry configured to: initiate output of audio and/or visual content; determine, based on one or more first short-range wireless discovery signals received from each of one or more other apparatuses in a vicinity of the data processing apparatus when output of the content is initiated, an identity of each of the one or more other apparatuses; and determine, based on one or more second short-range wireless discovery signals received from each of the one or more other apparatuses, whether any of the one or more other apparatuses are no longer in the vicinity of the data processing apparatus; and when any of the one or more other apparatuses are no longer in the vicinity of the data processing apparatus, pause output of the content.