I changed ATVs audio output to DD and got 5.1 from TVs optical.

I have another question about volume control in 861, is it inside digital domain or not?

I want to add my non Meridian subwoofers and surround speakers with MiniDSP 2x4HD over coax to optical converters.

Will I have volume control of these external devices or not?

HD621 , 800v4, 861v4, DSP7000, DSP5200HC