@mi-fu oh thank you very much for having done the test. May I ask you something. Have you verified that the led near the USB Audio Input was red and not blue (on the NX4 DSD of course) when playing the DSD? I've been caught myself, thinking it was native DSD format while actually the source had converted it to PCM.
The both native dsd and dsd over pcm are tested and it does not have the issue you described.
so most likely your ripper/player has a misconfiguration.