Black Magic audio capture

Hello Cows

FCP 6.0.6
MacPro Quad processor
OS X 10.5.8
Black Magic DeckLink HD Extreme (2009 version, current driver)

Most of my work is with DigiBeta in & out, via SDI, in uncompressed SD

The "BlackMagic NTSC-8 bit" uncompressed easy setup only gives me the option of capturing all 16 channels of audio. Can't modify it in the capture settings to 4 channels (or anything else). Can't select anything other than 16 channels when I try to make a new setup.

So I have to log the clip(s), then modify the clip settings to 4 channels, then batch capture.

This can't be right. What am I missing?

(Sorry if this is in the wrong forum - just move me to the BlackMagic forum if needed.)

Thanks for any help.