{TAIL ~ The control unit} controls {HEAD ~ the audio signal processing unit} to adjust the volume control values for the audio output port by the volume control buttons when the external audio reproduction unit is plugged in the audio output port 
{ TAIL ~ The control unit } controls { HEAD ~ the audio signal processing unit } to adjust the volume control values for the audio output port by the volume control buttons when the external audio reproduction unit is plugged in the audio output port
TAIL TAIL TAIL TAIL TAIL TAIL TAIL 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 OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH