Use PulseAudio to handle the sound system

PulseAudio is a powerful sound system that manages all the sound devices in your system.

PulseAudio is a general purpose sound server intended to run as a middleware between your applications and your hardware devices, either using ALSA or OSS. It also offers easy network streaming across local devices using Avahi if enabled.

https://wiki.archlinux.org/title/PulseAudio

Audio Layout

I have three speakers. Speaker A is directly connected to the motherboard audio card. Speaker B is connected to a monitor and then to the GPU through DisplayPort. In addition, I have a monitor that has an embedded speaker.

I want to use Speaker B as my default speaker to play music.

PulseAudio configuration

Normally, you can use a graphic interface of PulseAudio. There’re many of them in AUR. But today, I only want to solve the problem with its command line interface.

First, check all the interfaces you have in your system discovered by PulseAudio.


❯ pacmd list-cards
3 card(s) available.
    index: 0
	name: <alsa_card.usb-MACROSILICON_2109-02>
		....
    index: 1
	name: <alsa_card.pci-0000_07_00.1>
	driver: <module-alsa-card.c>
	owner module: 7
	properties:
		....
		device.product.name = "GA102 High Definition Audio Controller"
		profiles:
		output:hdmi-stereo: Digital Stereo (HDMI) Output (priority 38668, available: unknown)
		output:hdmi-stereo-extra1: Digital Stereo (HDMI 2) Output (priority 38468, available: unknown)
		....

So I got my card name <alsa_card.pci-0000_07_00.1>. I also got the profile using Speaker B (connected to the HDMI 2 interface) named output:hdmi-stereo-extra1.

Now, if I want to switch to Speaker B, I can use the following command:


pactl set-card-profile alsa_card.pci-0000_07_00.1 output:hdmi-stereo-extra1

If I want to make the config permanent, I can edit the file /etc/pulse/default.pa, and add to the bottom.


 set-card-profile alsa_card.pci-0000_07_00.1 output:hdmi-stereo-extra1