How can I make GP select Song A in Song Master when Song A is selected in GP?

[tripleB]

OK, here we go:

0. install Blackhole 2ch
1. Create an aggregate device (“Hauptgerät”) with Blackhole as first device, your audio interface as 2nd device, drift compensation on

2. set the output off Song Master Pro to Blackhole
   

   

3. use the aggregated device as GP input device, your audio interface as output device
   

   

4. set up your wiring:

Channel 1+2 provide the Song Master output, the following channels provide the input of the audio interface

5. enjoy!