Had this about a month now and was going through the settings and in the audio settings there is an option called "downmix" and it says " Set whether to apply Dolby Surround to the output audio signal" you then have the choice of stereo or surround. I have an av receiver which delivers 5.1 surround sound which works fine. I currently have it set on stereo, I guessed the surround signal would be sorted by the amp so chose not to let the blu ray do it. Is that correct?