I control Roon (1.3/276) primarily through my iPad, no problem with that. Sometimes I listen to music sitting in front of my iMac and wish to control the volume from the keyboard, but I can’t find a Roon setting that would allow this. Besides the “fixed” setting all others only make volume controllable from Roon remote (iPad).
Roon > Dirac Audio Processor stereo > Built in output
I’m not 100% sure why the keyboard volume keys don’t work in in Roon, but I suspect it has something to do with all the different possibilities for volume control that are inherent in any Roon-centric system.