attaching an external USB preamp (Aardvark) to divi 001

Hey.



I'm having trouble connecting the preamp to the digi 001 interface; getting no signal at all. Of course I need to do to boost the signal for inputs 3 and 4 at the back of the interface, and I understand I need to configure this somehow in the I/O settings, but It's unclear how.



Any help would be greatly appreciated.



Cheers,

Giles