A partner microphone unit (PMIC) configured to pick up sound from a target sound source, the sound s comprising a voice of a person, the partner microphone unit (PMIC) comprising • antenna and transceiver circuitry (ANT, RF-Rx/Tx) for establishing an audio link to another device, • a multitude of input units IU i, i=1, 2,..., M, M being larger than or equal to two, each input unit comprising a microphone for picking up sound from the environment of the partner microphone unit (PMIC) and configured to provide corresponding electric input signals (X 1,..., X M), each electric input signal comprising a target signal component and a noise signal component; • a voice activity detector for estimating whether or not or with which probability a voice of the person is present in the current sound from the environment and providing a voice activity control signal indicative thereof, or is configured to receive such voice activity control signal from another device; • CHARACTERIZED IN THAT the partner microphone unit further comprises a multi-input unit noise reduction system for providing an estimate S of the sound s comprising the person's voice, the multi-input unit noise reduction system comprising a multi-input beamformer filtering unit operationally coupled to said multitude of input units IU i, i=1,..., M, and configured to determine filter weights for providing a beamformed signal, wherein signal components from other directions than a direction of the sound source are attenuated, whereas signal components from the direction of the sound source are left un-attenuated or are attenuated less relative to signal components from said other directions; wherein the multi-input beamformer filtering unit comprises an adaptive beamformer, and wherein the multi-input unit noise reduction system is configured to • estimate a noise power spectral density of disturbing background noise when the voice of the person is not present, or is present with probability below a predefined level, or to receive such estimate from another device, and to • adaptively estimate a current look vector d (k, m) of the beamformer filtering unit for a sound originating from a sound source located at a specific location relative to the person wearing the partner microphone unit (PMIC), wherein the specific location relative to the person is the location of the person's mouth. • antenna and transceiver circuitry (ANT, RF-Rx/Tx) for establishing an audio link to another device, • a multitude of input units IU i, i=1, 2,..., M, M being larger than or equal to two, each input unit comprising a microphone for picking up sound from the environment of the partner microphone unit (PMIC) and configured to provide corresponding electric input signals (X 1,..., X M), each electric input signal comprising a target signal component and a noise signal component; • a voice activity detector for estimating whether or not or with which probability a voice of the person is present in the current sound from the environment and providing a voice activity control signal indicative thereof, or is configured to receive such voice activity control signal from another device; • CHARACTERIZED IN THAT the partner microphone unit further comprises a multi-input unit noise reduction system for providing an estimate S of the sound s comprising the person's voice, the multi-input unit noise reduction system comprising a multi-input beamformer filtering unit operationally coupled to said multitude of input units IU i, i=1,..., M, and configured to determine filter weights for providing a beamformed signal, wherein signal components from other directions than a direction of the sound source are attenuated, whereas signal components from the direction of the sound source are left un-attenuated or are attenuated less relative to signal components from said other directions; • estimate a noise power spectral density of disturbing background noise when the voice of the person is not present, or is present with probability below a predefined level, or to receive such estimate from another device, and to • adaptively estimate a current look vector d (k, m) of the beamformer filtering unit for a sound originating from a sound source located at a specific location relative to the person wearing the partner microphone unit (PMIC), wherein the specific location relative to the person is the location of the person's mouth.