We have found that audio from our FireWire interfaces will not show up in video editing software on a Mac, such as iMovie. Our testing has led us to believe that this problem isn’t specific to our interfaces, however it only affects FireWire devices. USB audio interfaces don’t seem to experience this issue.
The problem appears to be that the video engine in the host (i.e the computer) needs to be the sync master. This isn’t a problem for a host-based protocol such as USB, however with a peer-to-peer protocol such as FireWire, the FireWire device itself has to be the sync master.
The only solution at this time seems to be to use this software with a USB audio interface, such as the Saffire 6 USB.