[PD] M-Audio interface on Mac OS X can't hear PureData output

Hi,

I have an M-Audio FireWire 410 interface with latest drivers for Mac OS X. I can't hear my PureData application via the audio interface, the sound goes straight to built-in speakers output.

The M-Audio FireWire 410 is definitely chosen as output ok in the Mac Audio utility, and I can hear output from other apps (like iTunes) fine via the M-Audio interface (line and headphones).

Is there anything other than [dac~] I should use ?

Or are there other setting I need to use to ensure PureData detects the system audio settings ?

BTW I have tried restarting the PureData application after changing system audio settings, it makes no difference, it always seems to use the internal built-in speakers on my MacBook Pro.

thanks,

Darren