MEMS loudspeaker for generating sound waves in the audible wavelength spectrum, with a support element , a membrane deflectable with respect to the support element along a z-axis, at least one piezoelectric actuator supported on the support element for deflecting the membrane , designed as a cantilever arm and having a fixedly clamped end and a freely oscillating free end, a stroke structure via which the actuator is connected to the membrane , an electronic control unit for driving the actuator , at least one piezoelectric position sensor , which is integrated into the cantilever arm and by means of which the control unit can be provided a sensor signal that is dependent on the membrane deflection,and an elastic connecting element which connects a free end of the position sensor , which is integrated in the actuator designed as a cantilever arm , to the stroke structure ; wherein the control unit is designed in such a manner that the control unit performs a functional self-test process automatically, during the functional self-test process, the control unit controls the actuator with a reference actuator signal , with which the control unit compares a sensor signal with a reference signal stored in the control unit to obtain a comparison result , in which the control unit detects differences in the behavior of the MEMS loudspeaker by comparing the sensor signal with the reference signal when a deviation is detected, namely a reduction in performance due to aging or external influences, and in which the control unit , by taking into account the comparison result , henceforth operates and controls the actuator in a controlled manner with a higher electrical voltage compensating the reduction in performance when a reduction in performance is detected. with a support element , a membrane deflectable with respect to the support element along a z-axis, at least one piezoelectric actuator supported on the support element for deflecting the membrane , designed as a cantilever arm and having a fixedly clamped end and a freely oscillating free end, a stroke structure via which the actuator is connected to the membrane , an electronic control unit for driving the actuator , at least one piezoelectric position sensor , which is integrated into the cantilever arm and by means of which the control unit can be provided a sensor signal that is dependent on the membrane deflection,and an elastic connecting element which connects a free end of the position sensor , which is integrated in the actuator designed as a cantilever arm , to the stroke structure ; wherein the control unit is designed in such a manner that the control unit performs a functional self-test process automatically, during the functional self-test process, the control unit controls the actuator with a reference actuator signal , with which the control unit compares a sensor signal with a reference signal stored in the control unit to obtain a comparison result , in which the control unit detects differences in the behavior of the MEMS loudspeaker by comparing the sensor signal with the reference signal when a deviation is detected, namely a reduction in performance due to aging or external influences, and in which the control unit , by taking into account the comparison result , henceforth operates and controls the actuator in a controlled manner with a higher electrical voltage compensating the reduction in performance when a reduction in performance is detected. <EOS>