A microphone has a microphone capsule, wherein the microphone includes a test arrangement, the test arrangement including an undervoltage detector, a test signal generator unit and an adder. The microphone capsule may be connected to the adder via a first electrical line, a supply voltage line being connected to the undervoltage detector via a second electrical line. In the undervoltage detector the operating DC voltage of the microphone may be comparable with an internal reference DC voltage, the undervoltage detector being electrically connected to the test signal generator unit, and the test signal generator unit may be electrically connected to the adder.