How to Route Audio from GarageBand to CASTER

Setup GarageBand Input/Output:

Open GarageBand.
On the top left menu open GarageBand->Preferences
Click on the “Audio/Midi” tab.
Set the Output Device to “CASTER”

Leave the input Device set to your audio interface.

Setup CASTER application:

Open CASTER application – installed in your Application folder.

Hit the Add application button and Add GarageBand to CASTER tracks: