A multi-channel audio playback apparatus including a channel interface, a first switching amplifier and a second switching amplifier is provided. The channel interface is used to receive multi-channel digital data and generate first channel digital data and second channel digital data. The first switching amplifier is used to convert the first channel digital data into a first pulse width modulation (PWM) signal according to a first reference signal with a first frequency. The second switching amplifier is used to convert the second channel digital data into a second PWM signal according to a second reference signal with a second frequency. The second frequency is different from the first frequency.