Abstract: The invention provides an audio/video amplifier comprising an AV-signal receiver for receiving the signals from one or more program sources; a post-processing circuit connected with said AV-signal receiver for processing audio/video signals of said program source(s) or controlling the volume thereof; a microprocessor for controlling said AV-signal receiver and said post-processing circuit; an auxiliary power supply for powering said AV-signal receiver and said microprocessor; a main power supply controlled by the microprocessor for powering said post-processing circuit; and a signal identifying/comparing module arranged between said AV-signal receiver and said microprocessor for identifying and comparing input AV signals and outputting the result to the microprocessor.