HDCD, Digital Out or Thru DAC?

Where is your HDCD processor? If I remember right, you're running an HDCD-ready Rotel for your HDCD processing, and since HDCD operates in the digital world it has to see those extra bits in a digital signal.

Try looking around here: http://www.hdcd.com/
There's a setup/commections page that will answer your questions in depth.

Thank you!