Help- MBox- input grayed in Mix window

[muckle]

I'm new here, so don't laugh. I just hooked up my Mbox for the first time.
Going thru "Basics Guide". Start new session. Create new mono audio track.
Then go to Mix window and under the 'input' button both 'interface' and 'bus'
are grayed out.
I'm on a G5/dual OSX 10.3.8. System profiler sees the MBox (shown by name).
What am I missing?

[yOkO]

if you press it, does the output choice appear?

[muckle]

I tried that. Nothing happens.
Maybe a clue, but where the documentation shows a button
to the right of the "R" record button there's nothing.
I think that's what a Midi track looks like. But I made
sure it was a new Audio track (I've done it about 12 times).

[Flamethrower]

There have to be active inputs paths for them to show up as an input option. To check this, open the menu: Setups > I/O Setup. Click the Input button at the top of the pop up window. Click the Default button on the lower right which should set up Mic/Line 1-2 as an input path. Click OK at the bottom and you should be able to select that path as an input.

You can set up your buses in that same I/O Setup window, under the Bus page. Same thing.... click the Default button, then OK.

In the I/O window you can customize your inputs, outputs, number of buses, etc.... You can name your buses by double-clicking on their title and name them "Reverb" or "Delay" or any other name. Pretty handy.