@adasdad tbh overall I like roon and don't use the dsp functions either.
i went from roon core on a windows pc to roon core on a nas to the nucleus plus. One of the primary reasons why i went with the nucleus was the mutichannel output over hdmi, which i occasionally use in my movie room. That said for some reason on the odd occasion I want to use multichannel, nothing comes out of the hdmi and required reboots. A pain as that requires pulling the rack out of the cupboard etc.
Since it's now been unplugged for a day I'll retry it but don't have high hopes. Looks like it will need to go back to roon for a fix.