Looks like the Zenith might not support DSD Native with the DirectStream. See https://innuos.com/kb/known-compatible-native-dsd-dacs/
In general, DSD Native is somewhat of a crapshoot. Might want to try DoP mode - it packages up the DSD in a PCM container which is just as good as 'native' and seems to enjoy wider compatibility. I can't find any info on how to enable it on the Innuos website and don't own a Zenith.