umount channels
amixer set Master 75 unmute amixer set PCM 75 unmute amixer set IEC958 100 unmute # save settings alsactl store # test aplay /usr/share/sounds/alsa/Noise.wav
Backlist HDMI sound modules from display
echo "blacklist snd_hda_codec_hdmi" | sudo tee -a /etc/modprobe.d/blacklist.conf