ASUS Maximus Z790 Hero (ALC4082) - USB Audio 5.1 speakers assigned incorrectly and subwoofer not working

[Gess79]

I hope I'm correct to post this here. Still new to things Linux.

Situation
OS: Kubuntu 24.04
Mainboard = ASUS ROG Maximus Z790 Hero
USB Audio = 0b05:1a53 ASUSTek Computer, Inc. USB Audio
Speakers = Logitech Z906 Surround
Kernel = 6.8.0-40-generic
Alsa version = 1.2.9

Issue
The speakers seem to be assigned incorrectly and the subwoofer isn't working. I'm testing the speakers through pulseaudio as follows:

I'm listing the results below in three categories:

• The icon clicked within pulseaudio
• The soundfile played
• The speaker the sound is actually output to

Icon clicked - Soundfile played - Physical speaker output
Front Left - Front Left - Front Left
Front Center - Front Center - Rear Left
Front Right - Front Right - Front Right
Rear Left - Rear Left - Front Center
Subwoofer - Rear Center - Rear Right
Rear Right - (nothing) - (nothing)

I've had a lengthy discussion on Reddit but I couldn't find a fix for it so far: https://www.reddit.com/r/linux4noobs/comments/1980uv1/comment/kieqsor/

I'm happy to provide all information necessary to pinpoint the issue and fix it.

[Gess79]

I was able to resolve the issue by creating a separate config file for wireplumber. Details can be found here: https://www.reddit.com/r/linux4noobs/comments/1980uv1/comment/lnuzuf3/?utm_source=share&utm_medium=web3x&utm_name=web3xcss&utm_term=1&utm_content=share_button

[perexg]

ALSA reports channel positions using API - to check - use amixer -c 0 controls - look for chmap-variable lines. If the mapping is correct for your kernel, you should consult this with pipewire developers.