[bassmutant]

I have a firewire audiophile and am running a Macbook Pro with 10.4.7. The current driver from m-audio for my particular card works. These are the steps I used.
Install Software, interface is unplugged.
Power off.
Plugin Interface and power interface on. Do not chain anything else to the system on the firewire port as it will probably update your firmware, and my system seems to hang when I had drives chained to the audiophile until the fw update had been done.
Turn on computer.
Interface's firmware should be updated, then using the m-audio control panel, your device should be available. Don't forget to swap your output devices over in the Applications/Utilities/Audio Midi Setup App.
That's all I can say. Good luck.