A system including: an electronic memory device and a processor. The processor is configured to: control a communication device to receive first input information indicating a first instruction, the first instruction corresponding to control of sound associated with at least one first sound source; control a transmitter of the communication device to transmit first information to an audio output device, the first information corresponding to the first input information indicating the first instruction; control the communication device to receive second input information indicating a second instruction corresponding to control of sound associated with the at least one second sound source; and control the transmitter to transmit second information to the audio output device, the second information including or corresponding to an audio signal associated with the at least one second sound source and processed according to the second input information indicating the second instruction.