An accessory device for a mobile telecommunications terminal is disclosed, wherein the mobile telecommunications terminal comprises means for media processing and means for connecting to the accessory device. The accessory device comprises circuitry adapted to provide media transferring capabilities, a memory comprising at least one pre-stored parameter value related to the media processing capabilities of the mobile telecommunications terminal and for use by the mobile telecommunications terminal, and transfer means for transferring the at least one parameter value from the memory in the accessory device to the mobile telecommunications terminal via the connecting means.