I am thinking of purchasing Avid MediaComposer (basically to broaden my skillset) and downloaded the free 30 day trial so I can make sure it works on my system before I shell out $2K for it. After installing it twice (as it was freezing during the Audio Initialization screen I uninstalled it, re-downloaded and re-installed) I figured out that the problem is that I am using a PreSonus Firebox to run my KRK VXT4 speakers. If I start MediaComposer with the PreSonus plugged in, it freezes at the Audio Initialization screen. If I disconnect the PreSonus' Firewire connection, MediaComposer starts up beautifully (but then I am stuck with the internal speaker of my MacPro). For fun I tried plugging in the PreSonus after MediaComposer was already launched and it crashed MediaComposer. Is there some sort of set up I'm supposed to do to make MediaComposer play nice with PreSonus Firebox, or are the two mutually incompatible? Thanks for your help!