A digital mobile phone network infrastructure includes a plurality of radio base stations in communication with a plurality of mobile communications devices over a radio interface. In a method according to the invention packetized streamed media data is buffered within the network infrastructure and this data is then sent to a mobile communications device when traffic across the radio interface is low. The data may be transmitted at a lower than usual quality of service. Preferably the mobile communications device buffers the streamed data until reception is complete before the data stream is played to a user. Aspects of the invention also include a mobile communications device and a streamed media data controller for implementing the method. The method allows more efficient use of a network capacity and in particular allows the provision of high quality multimedia bulletins to mobile phone users at times of peak loading.