There is provided a method and corresponding apparatus for determining a beamforming configuration for a multi-antenna system according to an embodiment. In general, the multi-antenna system has at least two antennas and a port-to-antenna mapping between antenna ports and antennas. The method comprises obtaining (S1) first feedback information originating from a wireless device relating to a multi-antenna transmission based on a first beamforming configuration including a first port-to-antenna mapping, and obtaining (S2) second feedback information originating from the wireless device relating to a multi-antenna transmission based on a second, different beamforming configuration including a second, different port to-antenna mapping. The method also comprises determining (S3), based on the first feedback information and the second feedback information, a third beamforming configuration for the multi-antenna system including a third port-to-antenna mapping to enable beamforming according to a third beam form.