Play 1.0 audio as stereo when "Output stereo to all speakers" is selected

At the moment, 1.0 audio is played through the centre speaker only when "Output stereo to all speakers" is enabled (on a five speaker setup, under Windows XBMC 12.0). With the "Output stereo to all speakers" option disabled, 1.0 audio plays through the front speakers as expected. It would be good if XBMC could disable this option when a video file with 1.0 audio is being played so that the audio playback will make use of the front speakers instead of the centre speaker only.

Thanks.