Archlinux内置了asla，所以只需要安装用来调整配置的Sound servers就可以了。根据Arch Wiki的写法，选择了pulseaudio。pacman安装完之后只是有了server，还需要配置界面pavucontrol和系统托盘pasystray。为了利用音量键调整声音，需要安装pulseaudio-ctl，然后在Settings-Keyboard里面设置快捷键。pulseaudio-ctl的用法：
1
2
3
4
5
6
7
8
9
/bin/pulseaudio-ctl {up,down,mute,mute-input,set,atmost,full-status} [n]
Where up and down adjust volume in ±5 % increments
Where up and down [n] adjust volume in ±n % increments
Where mute toggles the mute status on/off
Where mute-input toggles the input status on/off
Where set set the volume to [n] %
Where atmost only takes effect if current volume is higher than [n]
Where full-status prints volume level, sink and source mute state to stdout
如果是在xfce4下面，打开Settings-Session and Startup-Application Autostart，添加一个/usr/bin/pasystray的启动项就好了。
参考： [SOLVED] PulseAudio and volume buttons pulseaudio-ctl: vol+/- and mute from the shell or shortcut keys