Having same issues with SimAudio MOON ACE. Used to be able to control volume file via ROON apps. Now since a few days, stuck in “Volume control is fixed”. Seems that either an update or something on the ROON side changed as my firmware (1.20 ACE and 1.13 MiND) from MOON has been applied 2 weeks ago and was working fine.
In house also have a few bluesound powernode that I am still able to control volume.