Volume Step Adjuster allows you to adjust the increment/decrement step of your system volume when you use your multimedia keys. By default, this step is 2% or 4%, which may be not appropriate for high-precision setting. With Volume Step Adjuster you can set this volume step to any valid value, for example, you can set the volume step to 1% or even 0.1%. The real volume step resolution available depends on your device.
Note, however, that this tool only configures increment/decrement step....