Both you and edd_jedi with his Phonic Firefly, also posting today, have the same problem, so you're both going to get the same answer.
You have modern audio interfaces that don't have - because they don't need - any drivers.
Today's Macs ever since early OSX, use Apple Core Audio where audio devices are recognized as "class compliant" and are automatically treated as audio i/o. Since OS9 pre-dates that, there are no drivers or allowances for such in the Mac hardware.
There were (once upon a time) Steinberg ASIO (Audio Stream Input/Output) drivers for Macs (and still are for new Windoze) provided by the interface manufacturers but since it's only we the few, the proud, the brave using ancient obsolete Model-T computers, they don't bother to do that specially for us.
Not what you wanted to hear I know, but unfortunately it's reality.
