Up until Mac OS X Lion you could use a handy shortcut to increase and decrease the system volume by quarter steps by doing the following:
- Option + Shift + Volume Up to increase volume by a quarter step,
- Option + Shift + Volume Down to decrease volume by a quarter step.
But what if you are on Lion or later?
Well, there seems to be a script that restores most of the lost functionality on the Apple Support Communities – I have not given this a try myself but it has received rather positive feedback and worth a shot if you are missing these shortcuts since upgrading or fancied using these shortcuts now that you’re aware of them.