The default keybindings for the volume up and volume down keys are too granular.  On my hardware, when using headphones, the difference between "just a little too quiet" and outright auditory pain is a single keypress.

I'm filing this against 3.6.3, but I had the same issue since the 2.x days, at which point I tracked it down to a constant somewhere in g-s-d which hardcoded the adjustment per keypress to 10%.  At the time it was an even worse issue, because those keypresses mapped to a rotating dial, which was difficult to accurately control.  I mention this because the hardware seems to have been tuned to Windows' volume control behavior, which is much finer (I'd guess 1% adjustment per press, based on how difficult it is to achieve a noticable change when I boot into that OS on the same hardware.)