I recently switched to i3 after using GNOME for a few years. Unlike many window managers, i3 is very bare-bones and its default installation does not include functionality to manage audio through a graphical interface like you would in GNOME. I fixed the problem by modifying my i3 configuration instead of installing a graphical application such as gnome-control-center. Here is how I did it using PulseAudio.

Lets look at the easy part first: mute audio and increase/decrease volume. With a bit of Googling, you can actually find a lot of suggestions for how to do this. I chose to do it through i3 by mapping the F10, F11 and F12 keys to PulseAudio commands that mute, decrease volume and increase volume respectively. I added the following lines to my i3 config file:

bindsym $mod+F10 exec pactl set-sink-mute @DEFAULT_SINK@ toggle # Mute
bindsym $mod+F11 exec pactl set-sink-volume @DEFAULT_SINK@ -5%  # Up
bindsym $mod+F12 exec pactl set-sink-volume @DEFAULT_SINK@ +5%  # Down

The volume is increased/decrease by 5% for each time that the commands are issued. A small matter with PulseAudio is that you can actuall set the volume above 100%!

A slightly harder problem I had was to changing the output device. For example, my computer has two output devices for audio: a speaker and the headphones. I wanted an easy and quick way to change the output audio device (or sink in PulseAudio terminology) with a keystroke (or two). So I mapped the F9 key to execute a bash script which does just that. Here is the relevant line in my i3 configuration:

bindsym $mod+F9  exec ~/.config/i3/toggle_sink.sh

The script relies on PulseAudio commands and is relatively simple. It does three things:

  1. Query a list of possible output sinks.
  2. Update the current DEFAULT_SINK to the next available output sink in the previously queried list.
  3. Redirect all currently playing audio streams to the new DEFAULT_SINK.

The current DEFAULT_SINK is the sink that the mute and increase/decrease audio commands will affect. Also, simply changing the DEFAULT_SINK does not cause the currently playing audio to be automatically redirected to that sink.

Whenever the script is executed, all sound is redirected to the next sink in the list. So repeatedly pressing $Mod+F9 effectively lets me cycle through the audio output devices with a couple of keystrokes!

#! /usr/bin/env bash

set -eu

# Get the ID for the current DEFAULT_SINK
defaultSink=$(pactl info | grep "Default Sink: " | awk '{ print $3 }')

# Query the list of all available sinks
while read line; do
    index=$(echo $line | awk '{ print $1 }')

    # Find the current DEFAULT_SINK
    if grep -q "$defaultSink" <<< "$line"; then

    i=$(( $i + 1 ))
done <<< "$(pactl list sinks short)"

# Compute the ID of the new DEFAULT_SINK
newDefaultPos=$(( ($defaultPos + 1) % ${#sinks[@]} ))

# Update the DEFAULT_SINK
pacmd set-default-sink $newDefaultSink

# Move all current playing streams to the new DEFAULT_SINK
while read stream; do
    # Check whether there is a stream playing in the first place
    if [ -z "$stream" ]; then

    streamId=$(echo $stream | awk '{ print $1 }')
    pactl move-sink-input $streamId @DEFAULT_SINK@
done <<< "$(pactl list short sink-inputs)"