Mojo I think you’re right. You have to use the app.

But it could be used “ quasi “ thru DAC.

For example:

I play a CD in my CD player. Transport only via optical out to optical into Transformer. Signal goes thru DAC and out to receiver via rca out. Once I’ve picked the input in the app and have pre volume set ( In this case 100%) then my interactions are just with my CD player and receiver remote control. Not the app.

This is my interpretation of it anyway.

M60ti Hafler9505 & JFET Pre,Axiom Transformer. M3 Marantz PM7200 Dual 606 Denon 2700 M2 Yammy RX595