I came across a strange quirk of using the Focusrite 6i6 2nd Ed with Source Connect ‘Link’.
So I can route talkback mic and talent mic from within Logic X, I use the Source-Connect Link plugin which comes with Source-Connect.
Armed with the ‘ID’ number of the Source-Connect Link I have inserted, I can then route the audio in and out of the Link by selecting the ID number in the Audio Options of SC.
All fine except I have a strange problem where the output of SC will not route to the Link as expected if I select the Link ID when the previous selection was the Scarlett interface. The fix for me was to select the internal audio options for the input / output and THEN select link and for some reason that does it!