Hello @Benedikt_Gruyaert,
At this time, Oppo UDP-203 cannot stream DSD content via Network, you can read more regarding this limitation in the following thread: OPPO UDP-203 and UDP-205 now Roon Ready. As far as I’m aware, USB/HDMI connections do not have this limitation. I hope this helps but do let me know if you have any other questions!
Thanks,
Noris