Patent ID: 6928175

Claim:
An audio circuit comprising a sound source having an output for producing an audio signal, a primary connector, and a connector header, said primary connector being electrically coupled to said sound source output to receive the audio signal, said connector header comprising: a header first contact electrically coupled to the sound source output; a header second contact electrically coupled to said primary connector; and a header ground contact that is electrically coupled to a ground; each one of said header first contact and said header second contact being ungrounded; said audio circuit adaptable to include a secondary connector circuit having a secondary connector and comprising: a secondary connector first contact electrically coupled to said header first contact; a normally-open secondary connector second contact electrically coupled to said header second contact; and a normally-open switch electrically coupled to said header ground contact; said switch being operable to electrically couple said header second contact to said header ground contact to short said primary connector to said ground while said switch is in its closed position; said audio circuit being operable in each one of a first configuration that does not include said secondary connector circuit and a second configuration that includes said secondary connector circuit.