A sink device is bi-directionally communicably connected to the source device. The sink device includes a first memory, and a controller. Stored in the first memory is a plurality of pieces of audio format information including information representing an audio format that the sink device can process. The controller selects, from among the plurality of pieces of audio format information stored in the first memory, one piece of audio format information corresponding to receiver format information representing an audio format that a receiver device connected to the sink device can process. The controller then outputs the selected audio format information to the source device.