This is the first (as until now for me only known) bigger (professional) player without the ability to select sound card output.
Perhaps I'm the only of few persons that uses multiple sound cards (and multiple speakers; monitor and real 5.1 system), but this way it is a good way to ensure that no unwanted sound (like error, system sound, or IM message) will be heard (with immerse loud) during the playback of a movie.