This is not a kernel bug but a missing UCM matcher. Result: with the matcher below and latest alsa-ucm-conf files, speakers and microphone work on my ASUS Zenbook S 14 UX5406SA.
Tested on: - Ubuntu 25.10 beta (up-to-date live session 26-9-2025) - LATEST files of https://github.com/alsa-project/alsa-ucm-conf as per 26-9-2025 CardLongName: ASUSTeKCOMPUTERINC.-ASUSZenbookS14UX5406SA_UX5406SA-1.0-UX5406SA Root cause: Upstream master does not contain a matcher for this CardLongName, so no UCM profile is loaded (-> “Dummy Output”). Adding the matcher below and updating the sof-soundwire profile (which already includes cs42l43/cs35l56) load and audio works. Fix (new matcher, to be added as ucm2/conf.d/sof-soundwire/ASUS- Zenbook-S14-UX5406SA.conf): # /usr/share/alsa/ucm2/conf.d/sof-soundwire/ASUS-Zenbook-S14-UX5406SA.conf SectionDefaults."sof-soundwire" { Condition { Type Regex CardLongName "ASUSTeKCOMPUTERINC.-ASUSZenbookS14UX5406SA.*" } Include.conf "sof-soundwire/sof-soundwire.conf" } Verification (files actually loaded), gathered with: strace -f -e trace=%file -o /tmp/ucm.trace \ alsaucm -c sof-soundwire list _verbs >/dev/null 2>&1 grep -oE '/usr/share/alsa/ucm2/[^"]+' /tmp/ucm.trace | sort -u /usr/share/alsa/ucm2/Intel/sof-hda-dsp/dsp.conf /usr/share/alsa/ucm2/blobs/sof/product_configs/ASUSTeK COMPUTER INC./ASUS Zenbook S 14 UX5406SA_UX5406SA.conf /usr/share/alsa/ucm2/blobs/sof/user_configs/ASUSTeK COMPUTER INC./ASUS Zenbook S 14 UX5406SA_UX5406SA.conf /usr/share/alsa/ucm2/codecs/cs35l56/init.conf /usr/share/alsa/ucm2/codecs/cs42l43/init.conf /usr/share/alsa/ucm2/codecs/hda/hdmi.conf /usr/share/alsa/ucm2/common/ctl/led.conf /usr/share/alsa/ucm2/common/pcm/hdmi.conf /usr/share/alsa/ucm2/conf.d/sof-soundwire/ASUSTeKCOMPUTERINC.-ASUSZenbookS14UX5406SA_UX5406SA-1.0-UX5406SA.conf /usr/share/alsa/ucm2/conf.d/sof-soundwire/sof-soundwire.conf /usr/share/alsa/ucm2/lib/card-init.conf /usr/share/alsa/ucm2/lib/ctl-remap.conf /usr/share/alsa/ucm2/lib/generic.conf /usr/share/alsa/ucm2/sof-soundwire/Hdmi.conf /usr/share/alsa/ucm2/sof-soundwire/HiFi.conf /usr/share/alsa/ucm2/sof-soundwire/cs35l56.conf /usr/share/alsa/ucm2/sof-soundwire/cs42l43.conf /usr/share/alsa/ucm2/sof-soundwire/dmic.conf /usr/share/alsa/ucm2/ucm.conf Request: Please add this matcher upstream (alsa-ucm-conf) so ASUS Zenbook S 14 UX5406SA works out-of-the-box. Happy to test any proposed patch or provide another `apport-collect` with this fix applied. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/2125284 Title: ASUS Zenbook S14 UX5406SA (Lunar Lake): no internal audio – cs42l43/cs35l56 report missing power supplies (“using dummy regulator”) on Ubuntu 25.10 beta (kernel 6.17) To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/alsa-driver/+bug/2125284/+subscriptions -- ubuntu-bugs mailing list [email protected] https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
