An audio beamforming apparatus comprising: a receiving circuit for receiving signals from an at least two-dimensional microphone array comprising at least three microphones; a reference circuit for generating at least three reference beam signals from the microphone signals received from the receiving circuit; a combining circuit for generating an output signal corresponding to a desired beam pattern by combining the reference beam signals in response to a first direction of a desired sound source and a direction estimate of an interfering sound source; an estimation circuit configured to generate said direction estimate by: determining a first angle corresponding to a local minimum of a power measure of the output signal in a first angle interval, the power measure being an angular function of the direction estimate; determining a second angle corresponding to a local minimum of the power measure of the output signal in a second angle interval; and determining said direction estimate as an angle selected from a set of angles corresponding to local minima of the power measure of the output signal, the set of angles comprising at least the first angle and the second angle; and wherein the combining circuit is arranged to determine combination parameters for the combining of the reference beam signals to provide a notch in the desired beam pattern at an angle corresponding to the direction estimate and a maximization of a directivity cost measure, the directivity cost measure being indicative of a ratio between a gain in the first direction and overall power gain averaged over all directions. a receiving circuit for receiving signals from an at least two-dimensional microphone array comprising at least three microphones; a reference circuit for generating at least three reference beam signals from the microphone signals received from the receiving circuit; a combining circuit for generating an output signal corresponding to a desired beam pattern by combining the reference beam signals in response to a first direction of a desired sound source and a direction estimate of an interfering sound source; an estimation circuit configured to generate said direction estimate by: determining a first angle corresponding to a local minimum of a power measure of the output signal in a first angle interval, the power measure being an angular function of the direction estimate; determining a second angle corresponding to a local minimum of the power measure of the output signal in a second angle interval; and determining said direction estimate as an angle selected from a set of angles corresponding to local minima of the power measure of the output signal, the set of angles comprising at least the first angle and the second angle; and determining a first angle corresponding to a local minimum of a power measure of the output signal in a first angle interval, the power measure being an angular function of the direction estimate; determining a second angle corresponding to a local minimum of the power measure of the output signal in a second angle interval; and determining said direction estimate as an angle selected from a set of angles corresponding to local minima of the power measure of the output signal, the set of angles comprising at least the first angle and the second angle; and wherein the combining circuit is arranged to determine combination parameters for the combining of the reference beam signals to provide a notch in the desired beam pattern at an angle corresponding to the direction estimate and a maximization of a directivity cost measure, the directivity cost measure being indicative of a ratio between a gain in the first direction and overall power gain averaged over all directions. <EOS>