An apparatus, comprising: a first input node configured to receive a first noisy input signal from a first microphone; a second input node configured to receive a second noisy input signal from a second microphone; a fixed beamformer module coupled to the first input node and coupled to the second input node; an adaptive blocking matrix module coupled to the first input node and coupled to the second input node; and an adaptive noise canceller coupled to the fixed beamformer module and coupled to the adaptive blocking matrix module, wherein the adaptive noise canceller is configured to output an output signal representative of an audio signal received at the first microphone and the second microphone, characterized in that: the apparatus comprises a noise correlation determination block configured to generate at least one estimated noise correlation statistic determined between the first noisy input signal and the second noisy input signal; and the adaptive blocking matrix module executes a learning algorithm by executing an adaptive filter that estimates an inter-sensor signal model between the first noisy input signal and the second noisy input signal based, at least in part, on the at least one estimated noise correlation statistic determined between the first noisy input signal and the second noisy input signal to output a noise signal, such that a noise correlation is maintained between the output of the fixed beamformer module and the noise signal output from the adaptive blocking matrix module as a consequence of the adaptive blocking matrix being based on the at least one estimated noise correlation statistic. a first input node configured to receive a first noisy input signal from a first microphone; a second input node configured to receive a second noisy input signal from a second microphone; a fixed beamformer module coupled to the first input node and coupled to the second input node; an adaptive blocking matrix module coupled to the first input node and coupled to the second input node; and an adaptive noise canceller coupled to the fixed beamformer module and coupled to the adaptive blocking matrix module, wherein the adaptive noise canceller is configured to output an output signal representative of an audio signal received at the first microphone and the second microphone, characterized in that: the apparatus comprises a noise correlation determination block configured to generate at least one estimated noise correlation statistic determined between the first noisy input signal and the second noisy input signal; and the adaptive blocking matrix module executes a learning algorithm by executing an adaptive filter that estimates an inter-sensor signal model between the first noisy input signal and the second noisy input signal based, at least in part, on the at least one estimated noise correlation statistic determined between the first noisy input signal and the second noisy input signal to output a noise signal, such that a noise correlation is maintained between the output of the fixed beamformer module and the noise signal output from the adaptive blocking matrix module as a consequence of the adaptive blocking matrix being based on the at least one estimated noise correlation statistic. the apparatus comprises a noise correlation determination block configured to generate at least one estimated noise correlation statistic determined between the first noisy input signal and the second noisy input signal; and the adaptive blocking matrix module executes a learning algorithm by executing an adaptive filter that estimates an inter-sensor signal model between the first noisy input signal and the second noisy input signal based, at least in part, on the at least one estimated noise correlation statistic determined between the first noisy input signal and the second noisy input signal to output a noise signal, such that a noise correlation is maintained between the output of the fixed beamformer module and the noise signal output from the adaptive blocking matrix module as a consequence of the adaptive blocking matrix being based on the at least one estimated noise correlation statistic.