https://wiki.archlinux.org/index.php/Alsa#Pops_when_starting_and_stopping_playback My ears were nearly wrecked by this awfulness. On a side note, the Conexant Audio CX20751/2 isn’t the best integrated sound card around. Even lowly Realteks have far better dynamic range and equalization. There is virtually no soundstage, mids are very muffled, even with headphones. It can be found on some lower end Thinkpads (e.g. S440/E440); considering that these are cheap SMB laptops it’s not surprising that they had to cut corners somewhere.