the OSX audio system does have a system to join two different soundcards -open Audio MIDI Setup (usually in the Utilities folder) -then open the Aggregate Devices Editor from the Audio menu - here you can create a new device, select which will be the master clock etc -this new device can then be selected and used in the usual manner
Yes! I have tried it and it seems to work now, as Pd recognizes this aggregate device, I have to do a detailed recording session, to exactly see how well suited it will be for the application Thanks this option really seems to works well!!
tania