To not increase PCM value when increasing volume with pulseaudio
When you use pulseaudio and you increase the volume, it will increase the front volume but also the PCM value leading to crackling sound when reaching value above 80%. Here is how to change this behaviour.
Edit /etc/pulse/default.pa and replace the line with load-module module-udev-detect with the following:
load-module module-udev-detect ignore_dB=1