When recalling a preliminary stored scene including parameter values regarding a plurality of input/output ports respectively receiving or outputting an audio signal with respect to outside, a plurality of transmission/reception ports respectively transmitting or receiving an audio signal with respect to another equipment via a network, a signal processing channel processing an audio signal, and a patch transmitting an audio signal among the plurality of input/output ports, the plurality of transmission/reception ports and the signal processing channel, a setting to leave parameter values defining connection between the input/output ports and the transmission/reception ports by the patch before the recall as they are can be performed by a particular group safe setting button.