A method of processing audio signals at a device, the method comprising: receiving audio signals, over a range of angles, at input means of the device, the audio signals including a primary signal received with a principal direction of arrival at the input means and at least one interfering signal received with a respective at least one interfering direction of arrival at the input means; determining a plurality of measurements for the received audio signals over the range of angles, each measurement relating to a particular angle and indicating the energy of the received audio signals which are received from the particular angle; for each angle over the range of angles, removing from the measurement for that angle a value based on the minimum of: (i) the measurement for that angle, and (ii) a corresponding measurement for a corresponding angle mirrored around the principal direction of arrival, whereby the remaining values of the plurality of measurements are indicative of said at least one interfering direction of arrival; wherein the step of determining a plurality of measurements comprises determining a range of beamformer outputs of beamforming means applied to the received audio signals when steered over the range of angles, and wherein the step of removing a value from the measurement for each angle over the range of angles comprises removing from the beamformer output energy for that angle a value based on the minimum of: (i) the energy of the beamformer output for that angle, and (ii) the energy of a corresponding beamformer output for a corresponding angle mirrored around the principal direction of arrival, whereby the remaining values of the plurality of beamformer outputs are indicative of said at least one interfering direction of arrival. receiving audio signals, over a range of angles, at input means of the device, the audio signals including a primary signal received with a principal direction of arrival at the input means and at least one interfering signal received with a respective at least one interfering direction of arrival at the input means; determining a plurality of measurements for the received audio signals over the range of angles, each measurement relating to a particular angle and indicating the energy of the received audio signals which are received from the particular angle; for each angle over the range of angles, removing from the measurement for that angle a value based on the minimum of: (i) the measurement for that angle, and (ii) a corresponding measurement for a corresponding angle mirrored around the principal direction of arrival, whereby the remaining values of the plurality of measurements are indicative of said at least one interfering direction of arrival; wherein the step of determining a plurality of measurements comprises determining a range of beamformer outputs of beamforming means applied to the received audio signals when steered over the range of angles, and wherein the step of removing a value from the measurement for each angle over the range of angles comprises removing from the beamformer output energy for that angle a value based on the minimum of: (i) the energy of the beamformer output for that angle, and (ii) the energy of a corresponding beamformer output for a corresponding angle mirrored around the principal direction of arrival, whereby the remaining values of the plurality of beamformer outputs are indicative of said at least one interfering direction of arrival.