A signal processing apparatus and a control method thereof are provided. The signal processing apparatus includes a signal processor which processes a video signal and/or an audio signal; a power supply which generates a power signal; a first connector configured to be connected with an external second connector; and a control circuit which outputs the video signal and/or audio signal and the power signal if the external second connector is connected to the first connector, and performs a shutoff operation to not output the power signal if the first connector is not connected to the external second connector.