An audio processing system and a method thereof are provided. The system includes an audio receiver and an audio processor device. The audio receiver includes an audio interface, an absolute value converter unit, a framing unit and a characteristic value detector unit. The audio interface receives an audio signal from an audio transceiver device. The absolute value converter unit takes an absolute value of the audio signal to output an absolute value audio signal. The framing unit divides the absolute value audio signal into a plurality of sub-frame signals. The characteristic value detector unit detects characteristic values of the sub-frame signals. The audio processer processes the audio signal outputted by the audio transceiver device according to the characteristic values of the sub-frame signals.