Nevermind I got it, :) . For those of you interested I just set different values into GPRM for each audio track, then had the play button on the main menu check to see which value was in memory. If it was value 1 then it palyed the stereo trailer followed by the movie with the stereo track, if it was value two it played the surround trailer followed by the movie with the surround track. I learn something new every day...