A method of adaptively mapping several microphone signals to a multi-channel audio signal, for example to capture stereo audio from a device held in variable orientations 110, 120. At least two microphone signals, from at least two spaced apart microphones, are obtained. A device orientation signal is obtained from a sensor, which may be on the device with the microphones. The microphone signals are adaptively mapped, based on the device orientation signal, to produce the channels of a multi-channel audio signal. The microphone signals may come directly from the microphones, and the audio signal may be output to a storage device. Alternatively, the microphone and orientation signals may be stored, and the mapping carried out during playback. The mapping may: be based upon microphone parameters; include a stereo widening process, a beamforming algorithm or adaptive noise cancellation; indicate that a primary microphone is oriented in the same direction as a camera; be performed once per recording or on an ongoing basis; and may be smoothed over a transition period. The method may be carried out on a device comprising an audio signal processor, which may be a dedicated chip.
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