Change default audio output

pepe

For some reason each boot always defaults to a speaker that doesn't work (or just doesn't output audio, idk which) and I want to chance it into always being the one that does work (the second option) unless I specify otherwise during the day. Noob question but eh, doesn't hurt to try :kekw: (<--on purpose)

zephyrus

Hey pepe,
When I run: cat /dev/sndstat
My output is:

Installed devices:
pcm0: <Realtek ALC256 (Front Analog Headphones)> (play)
pcm1: <Realtek ALC256 (Rear Analog Line-out)> (play)
pcm2: <Intel Kaby Lake (HDMI/DP 8ch)> (play) default
pcm3: <BEHRINGER UMC404HD 192k> (play/rec)

Each pcm entry is a detected sound device. The one marked default is the active device.

Your output will be different but still, you have pcm0, 1, 2 and so on.
Once you know which one you want to use, edit:
sudo (editor of your choice) /etc/sysctl.conf

When the conf file opens, change this line to the number you prefer:
hw.snd.default_unit=1 (which, as you prefer, is the "second" option)

I use XFCE but this should be the same in Mate. Maybe others can confirm this or provide additional instructions.

pepe

zephyrus
Huh, strange, can't find that line. Only "default_auto" but it says it's for switching when needed. I'll add it and see how it goes.

zephyrus

Here is my output for /etc/sysctl.conf
See the last line for reference:

`cat /etc/sysctl.conf

This file is read when going to multi-user and its contents piped thru
sysctl'' to adjust kernel values.man 5 sysctl.conf'' for details.

Uncomment this to prevent users from seeing information about processes that
are being run under another UID.
security.bsd.see_other_uids=0

add user mount
vfs.usermount=1

the following is required to run chromium browser
kern.ipc.shm_allow_removed=1

For Desktop use default for server is 80
kern.sched.preempt_thresh=224

Automatically switch audio devices (e.g., from HDMI to USB sound device when plugged in)
hw.snd.default_unit=2

// Please note that "2" is the correct setting for my PC as I use a DP cable and the speakers of the monitor.

Here is a tutorial which might help.

pepe

zephyrus

No, no. Mine seems to be different, instead of "default unit" it is "default auto". But changed that instead and kept the other one as a comment just in case.

zephyrus

You are correct. Originally, it does say "auto".
Commenting the original out is smart. But "unit" should work. 🙂