Audio/video processing unit and control method thereof

A home theater includes a main unit section and at least one speaker section. The main unit section includes a communication section which receives an AV stream from an AV stream transmission device and via a communication network, a demux section which separates the AV stream into a video stream and an audio stream, a video processing means which processes the video stream so as to generate a video signal, an audio processing section which processes the audio stream so as to generate an audio signal, and an audio acquisition section which acquires an audio stream which includes at least a part of the audio of the AV stream. The communication section transmits the audio stream acquired by the audio acquisition section to the speaker section, via the communication network.