The invention prevents unwanted sounds from being outputted from an AV output apparatus such as a HDTV receiver. In the invention, when a streaming signal of a predetermined format having video data and audio data is inputted to a streaming input terminal 10, separation unit 23 of a relay apparatus 2 separates this signal into the video data and audio data. HDMI transmitter 27 generates and outputs a streaming signal having the video data separated by the separation unit 23, of the same format as that of the streaming signal inputted to the streaming input terminal 10.