Thanks for the test. Could you try another thing: when playing PCM sound with WASAPI, could you try windows volume controls and mute/unmute: does this change actual output volume (not the numbers on the display) and mute the DAC? I do understand that then it’s not bitperfect output, but it’s good enough when watching TV/series/movie.
Why I’m asking is because I have a M2Tech Young MkIII, and it seems to be using the same XMOS, and the driver panel is very similar, just without Volume control. When playing music in WASAPI mode, volume control has no effect, even mute does not work. In the previous model (M2Tech Young DSD) the volume control was working (not in DoP mode), so the assumption is that MQA support removes XMOS chip volume control altogether.
Pro-ject Pre Box input stage seems to be very similar to M2Tech Young MkIII stage: both are XMOS, both support MQA, which is why I’d like to understand if MQA support prevents PCM volume control in WASAPI mode.