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+1
I'm also want that feature, as I use my Mac to directly send audio to a power amplifier (and thus manage volume at a system level), I need fine grained volume management, otherwise the volume is often too loud or too soft.
But I found a workaround, I didn't have the time to really test though :
Create a custom action, with an applescript function: (this one increases by step of 1
"
set current_volume to output volume of (get volume settings)
if current_volume is less than 100 then
set current_volume to current_volume + 1
end if
set volume output volume current_volume
"
(do not copy the double quotes, only what's inside)
You can decrease volume by 1 using :
" set current_volume to output volume of (get volume settings)
if current_volume is more of 0 then
set current_volume to current_volume - 1
end if
set volume output volume current_volume
"
As I said earlier, I haven't tested it yet (not at home currently), but it might work. But having the possibility to repeat the SHIFT+OPTION+Volume up/down would be easier (and also would bring the possibility to display the volume OSD.
I really hope the RB developpers implement it soon!