Windows' system volume has to be set to 100% too. Generally volume in both Media Center and Windows (or macOS or Linux) has to be set to 100% or else you'll just get noise as described. This can be an issue in setups without physical volume control for the speakers/headphones, which I would highly recommend either using a DAC with built-in volume control (e.g. iFi DACs) or add a potentiometer in the chain to control volume.
And you're outputting DoP over ASIO in that app there. Maybe try replicating that in MC or try using WASAPI instead since you're already using DoP.