Check you midi settings. They are hard to find. Maybe google it. Perhaps they are set to 24/96 and your dac only takes 16/44.
MacBook Pro settings for mini-toslink output
I'm interested in the NPR jazz night in America so I'm trying to play my mac through a luxman d-05 for the first time and getting no joy. Mini-toslink from mac headphone output to Luxman toslink digital input. I selected internal speakers optical digital output port on the mac and still no joy. What am I missing? Any help appreciated.