Abstract: The invention relates to a system and method which allows audio and/or video signals transmitted from a source device, such as an MP3/MP4 player to be transmitted to a host device such as speakers and/or a display screen via a wireless communication device. The system allows command signals generated from the source device and/or the wireless communication device to also be transmitted to the host device, and may receive data in return from the host device, said data typically indicative of at least one operating feature or parameter of the host device.