Multiple ways to control volume


My setup: Roon -> RoPiee -> ODAC -> Objective2 headphone amp. The volume slider in Roon control, through proxy, the (digital) volume of my DAC. I have a second analog volume control on my headphone amp. What would be the best setup? Should I choose I fixed volume in Roon, and set the DAC volume to 100%, or ‘just below 100%’ as the ODAC manual from JDS labs recommends? I guess this would lead to maximum resolution. Or doesn’t this matter and should I set the analog volume to maximum and control the volume via the slider in Roon? Any ideas?