Hello @Rudiger_Pfaender,
@Rugby and @ged_hickman1 are correct (thanks!), the Cambridge Audio CXNv2 does not process DSD natively regardless of the input source. Wether it is Roon Ready streaming or from a USB stick, the device will convert to high-resolution PCM before it reaches the DAC.
The “Roon Ready DSD Mode” option determines where the DSD to PCM conversion happens – on the device or on the Roon Core. When the device is configured for “PCM for Digital Output” the Roon Core will do the conversion in order to allow non-DoP capable DACs to output audio for DSD content.
-John