Sound on archlinux depends on alsa drivers, to enable it, you must install alsa utilites first on archlinux system.About ALSA:
The Advanced Linux Sound Architecture (ALSA) provides audio and MIDI functionality to the Linux operating system. ALSA has the following significant features:
- Efficient support for all types of audio interfaces, from consumer sound cards to professional multichannel audio interfaces.
- Fully modularized sound drivers.
- SMP and thread-safe design
- User space library (alsa-lib) to simplify application programming and provide higher level functionality.
- Support for the older Open Sound System (OSS) API, providing binary compatibility for most OSS programs.
open terminal then:
#pacman -S alsa-utils alsa-plugins alsa-lib
Then your sound should work. Try alsamixer
you should see like this, even if you in the terminal mode.
Use left, right, up and down for navigation, "M" button for mute and unmute. On LXDE you can add sound by adding Volume Control Panel item.
If you have two devices sound, HDMI and internal sound card, and your sound still not up, you must set the card devices into your internal sdcard.
Edit your /usr/share/alsa/alsa.conf, using GUI editor to make it easy.
$sudo leafpad /usr/share/alsa/alsa.conf
then press CTRL+F, then type card 0 or card 1.
If you want to set card 1, just change card 0 to card 1, and vice versa.
Then try volume control again, or alsamixer.