An audio mixing/reproducing device includes an audio decoder (11) configured to decode an encoded audio input signal, an audio mixer (13) configured to mix an audio signal output from the audio decoder (11) with a non-encoded external audio input signal, and an audio encoder (12) configured to encode an audio signal output from the audio mixer (13) to generate an encoded audio output signal, and in addition, a switch (14) configured to generate a switch signal for controlling operations of each of the audio decoder (11) and the audio encoder (12) in response to a switch activation signal. The audio decoder (11) and the audio encoder (12) each support a plurality of encoding schemes, and the switch (14), when switching the encoding scheme of the audio decoder (11) from a first encoding scheme to a second encoding scheme, controls the audio decoder (11) and the audio encoder (12) so that the encoding scheme of the audio encoder (12) is switched from the first encoding scheme to the second encoding scheme as in the audio decoder (11).