i did something like that: I bought a cable almost like this http://www.proaudiosuppliers.com/hosa-cmp-159.html. The difference is that all the edges are 3,5mm so i also bought two adaptor converters from 1/4" to 1/8". I connected these adaptors in the two jacks (L & R) of roland mt-32,then i connected the two edges of the 3,5mm cable in the adaptors and the other edge (the third) i connected it to the 'mic' jack of my mac. I don't hear a thing. What do i have to do? The roland all the time is showing midi messages (various titles of the music that plays) while the games are running. It seems that it is working.