Realtek ALC285 Volume Control Fix for ASUS GA403W
Hello! I am running Bazzite on my ASUS ROG Zephyrus G14 (GA403W) and have a persistent, ASUS audio issue that I need the correct kernel argument for.
The Problem: The master volume slider does not control the loudness; it only makes the audio muffled/distorted when lowered. The sound is clear only at 100%.
an oddity, this audio functionality worked perfectly on a previous Nobara installation, confirming that a specific custom patch exists but i could find how nobara did it.
Fixes Attempted : I have already tried all the standard rpm-ostree kargs fixes, including:
model=alc255-asus
model=headset-mode
model=asus-zenbook
The PipeWire soft-mixer configuration.
Request: Could you please look at the hardware IDs in my log and provide the exact custom rpm-ostree kargs --append='...' command needed for the ASUS GA403W's ALC285/Cirrus amplifier?
I should note im pretty new to linux and this is just what was suggested might fix it
My System Diagnostic Log:
https://paste.centos.org/view/6c3a3640
https://paste.centos.org/view/c0d20bf3
1 Reply
UPDATE: Root cause identified
After extensive debugging, I've found the exact problem:
Issue: The volume slider controls the ALC285 codec's Master volume instead of the CS35L56 amplifier volumes. This only affects signal quality (causing muffling) rather than actual loudness.
What works:
bashamixer -c2 sset 'AMP1 Speaker' 50% # ✅ Actually changes volume
amixer -c2 sset 'AMP2 Speaker' 50% # ✅ Actually changes volume
amixer -c2 sset 'Master' 50% # ❌ Only causes muffling
The CS35L56 amps ARE detected and working:
Firmware loading successfully (v3.11.16)
Volume controls exist (numid 6 and 12)
Manual control works perfectly
The problem: PipeWire/ALSA is using the wrong mixer controls by default. The AMP controls should be the primary volume, with codec controls locked at 100%.
What's needed: Either a kernel quirk for device ID 10431024, an ALSA UCM profile, or a PipeWire profile update to map the controls correctly.
Optimal config:
Master: 100%, Speaker: 100%
AMP1 Speaker: 85%, AMP2 Speaker: 85%