Device Volume vs Fixed Volume on LS50 Wireless

I have the original KEF LS 50W (roon tested) I have the option of both fixed volume and device volume. Setting to fixed doesn’t seem to actually change anything. (i can still change volume both on roon and the remote) If I use device volume is any sort of DSP or additional volume control being used? (this is what i want to avoid) Or does “device volume” just control the hardware volume in the KEF speakers themselves?

You are using a DSP speaker.

Yes, to see what’s happening/ not happening take a look at the Roon Signal Path screen.