I think this was discussed on facebook at one point- I didn't see if it was a software possibility or not. For live It would be pretty great to be able to give a sound engineer separate channels for drums and everything else.
Can't be done. There's only one D/A convertor. A few ideas have been discussed in relation to this, getting more outputs/cuing from the headphone jack or potentially getting more outputs from the USB.
All have been shut down.
So creative work-around's must be embraced.
Aha good to know, thanks!