Abstract: An all-in-one audio system includes an audio chip, an audio interface, first and second audio signal amplifiers, a speaker, a woofer, a multi-function controller, a high definition multimedia interface (HDMI), and a switch. The multi-function controller is connected to the audio chip, the switch, the audio interface, the first and second audio signal amplifiers, and the HDMI. When the multi-function controller detects a high definition multimedia signal through the HDMI, the multi-function controller turns off the switch, decodes the high definition multimedia signal into an audio signal, and transmits the audio signal to the audio interface, and the first and second audio signal amplifiers. The first and second audio signal amplifiers amplify the audio signal and output the amplified audio signal to the speaker and woofer.