hi,
I´m new to this forum. I´m from Austria and no native speaker.
So please be patient. i´m on the german version of OS X. So I´ll give it a try.
Maybe I don´t use the correct english terms.
I´m using the RME Fireface. Working with the Apogee should be close.
In the system preferences open the sound-panel. select your apogee interface as your output and input device.
Then open the Audio-Midi utility programm. Select your apogee interface.
In the down-right corner there should be a “speaker configuration” button. Press the button then select “more channels”. change from stereo to 5.1 or whatever you need. Now you can route different channels to different speakers.
does that make sense?
Hope it helps.
Greetings from Austria
wolfger