Pulseaudio command line mixer.

pamixer is like amixer but for pulseaudio. It can control the
volume levels of the sinks. Also, this project can provide you
a small C++ library to control pulseaudio.

Features
  - Get the current volume of the default sink, the default
    source or a selected one by his id
  - Set the volume for the default sink, the default
    source or any other device
  - List the sinks
  - List the sources
  - Increase / Decrease the volume for a device (using gamma
    correction optionally)
  - Mute or unmute a device

WWW: https://github.com/cdemoulins/pamixer