Tutorial: Cubasis To Cubasis Via Audiobus

Help I can’t get this to work!

I’ve loaded Cubasis into both the input & output parts of Audiobus before launching. However when I try to record some audio nothing comes out and ‘Audio Input’ is set to Audiobus with a ‘?’ below it. However if I add an effect to Audiobus it will work (but obviously via the middle app).

I’ve tried reinstalling both Audiobus and Cubasis & rebooted but still no luck. Any ideas?