I recently invested in a digital surround sound system, and have been enjoying digital surround sound through the TOSlink port of my Macbook Pro (Mid 2010 and Late 2011 models). However, I've noticed that when I'm playing two-channel sound (for instance, spotify), three of my five speakers are silent.
I used to have Logitech X-540's which have a 'matrix mode' which splits sound out over all the speakers. Is there any way to duplicate or partially duplicate this functionality with my Mac?