Hi Daniel,, thanks for the info...
Under windows i found the monitoring of the output in Digicheck invaluable for working on a mix, truly a top tool!!
I was surprised this seems to be an issue with core audio - and from RME support posts seem that it is something very tricky to get sorted!
Thanks for the how to,, im not familiar with the looback feature - is there a how to anywhere - or could someone kindly point me in the right direction.
All i would like to do at the moment is monitor the main output channels in digicheck - say - Analog outs 1-2.
cheers and thanks,,,, Rme always great support!!