To prevent temperature rise of an amplifier. An AV amplifier 1 that amplifies an audio signal includes a PWM modulator 5 that controls dynamic range of the audio signal to not more than a setting value, and a microcomputer 2 sets the setting value based on consumption current. The microcomputer 2 sets the setting value to a predetermined value (−35 dB) in case that state that consumption current is not less than a predetermined threshold (4.9 A or 3.6 A) continues for a predetermined time (2 minutes or 7.5 minutes).