In an exemplary embodiment of the present invention, the step of displaying the volume control menu window on the display unit converts {TAIL ~ the volume control menu window} on the display unit to {HEAD ~ a volume control menu window} for the speakers when the external audio reproduction unit is released from the audio output port 
In an exemplary embodiment of the present invention , the step of displaying the volume control menu window on the display unit converts { TAIL ~ the volume control menu window } on the display unit to { HEAD ~ a volume control menu window } for the speakers when the external audio reproduction unit is released from the audio output port
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH