I don't know where the problem is with this connection. Take a pair of good quality RCA cables and plug the red cable to the R port fixed output and the white one to the L port. Then on your Yamaha, plug the corresponded other end of the cable to either Audio1 or Audio2 plugs on the back. then inside the menu for your Yamaha, associate that plug to the source name that you want the DAC on.

The Marantz does have a variable output if you were planning on using the unit as a pre-amp, but as you have the Yamaha, then you would use the fixed output


Anthem: AVM60, Fosi DAC-Q5
Axiom: ADA1500, LFR1100 Actiive, QS8, EP500, M3, M3comp, M5