Understand Middle Control Panel

Learn about the middle part of main form, it's splited into five part.

Play Control and Zoom Control

	Play Audio
	Pause Audio
	Stop Audio
	Play Audio Loop
	Go ahead
	Fast back
	Fast next
	Go end
	Zoom out
	Zoom in

	Marker Controls
	Add Marker: add current audio play position as new marker Delete Marker: delete selected marker. Goto Selected Marker: set audio play position by select marker.
	Current Playing Audio's Position
	Current Playing Audio's extern position information
	Volumn setting