A system and method of audio/video streaming in which a server transmits over a network an audio/video stream to a client device. The client device is able to send command data to the server causing the server to provide a change in content of the audio/video stream from a first content to a second content. Buffers in the server and client device can be flushed or skipped-over at the time of sending the command data so as to improve response time and marker data can be sent from the server to the client device to indicate the start of the second content.