u182155

Hi there I am new to this. Just purchased a Stagescape M20d and 2 x L2t's. Intending to use this stuff live however also in my home studio. I have replaced my personus gear with this. I can't seem to get audio from my mac, i.e. basic playback of iTunes etc which the personus could do. Is someone able to point me in the right direction. Regards, Dave