To be easy for a user to judge difference of sound quality of an audio signal that is output in a balanced mode and sound quality of the audio signal that is output in an active control ground mode.A DAP 1 has a balanced mode and an ACG mode. In the balanced mode, an analog audio data is amplified by an amplifier 8, a negative-phase data of the analog audio data is amplified by an amplifier 9, and the amplified analog audio data and the amplified negative-phase data are mixed so as to be output. In the ACG mode, the analog audio data is amplified by the amplifier 8 and ground is maintained by the amplifier 9. The CPU 2 decreases volume of the analog audio data that is output in the balanced mode compared with volume of the analog audio data that is output in the ACG mode.