apport information
** Tags added: apport-collected staging stonking
** Description changed:
Hardware:
- Laptop: Samsung Galaxy Book6 Pro (device ID C910)
- Audio architecture: Intel SoundWire (SST), with one Cirrus CS42L45
companion codec and TWO Cirrus CS35L57 smart amplifiers
(SoundWire links: LW = l1u0, RW = l2u1)
- Windows/Samsung hardware ID: 144D:C910 -> Linux firmware SSID: 144dc910
Environment:
- Ubuntu 26.10 (development / "Stonking Stingray") tested from the
live USB session, all default settings
- Kernel: [FILL IN from log section 1]
- linux-firmware-misc: [FILL IN from log section 2]
Symptoms:
- Internal speakers sound flat, lack bass entirely, and get scratchy /
rattling at moderate volume
- The sound is NOT broken in Windows (Samsung applies Dolby Atmos +
amp/DSP processing there)
- Headphones are fine
- This reproduces on a clean live USB with zero changes made
- Installing the packaged amp firmware
(cs35l57-b2-dsp1-misc-144dc910.{wmfw,l1u0.bin,l2u1.bin},
shipped in linux-firmware-misc 20260915) did NOT change the sound
What I already verified:
- The correct per-SSID amp firmware IS present at
/usr/lib/firmware/cirrus/ (confirmed by ls -la, see attached log)
- Firmware being present does not fix the symptoms, so this appears to
be a board-enablement issue (SOF topology / sof_sdw quirk / UCM
routing) rather than missing firmware files
- sound/soc/intel/boards/sof_sdw.c has no Samsung DMI/SSID entry for
this machine, and no matching SOF topology or UCM profile appears to
exist
Diagnostic evidence:
- I am attaching the Windows Samsung audio driver INF
(xucsmeext_c910.inf, from the Windows DriverStore). It is direct
evidence from Samsung's own driver of the exact hardware:
CS35L57 x2 (SoundWire links l1u0 = left woofer, l2u1 = right
woofer) + CS42L45 codec, Windows hardware ID 144D:C910.
- I will attach the full Linux diagnostic log
(galaxybook6-audio-diagnostic.log) as soon as I can boot the live
USB again - happy to add it now if needed, just ask.
Expected behavior:
- Internal speaker output at least comparable in quality to Windows
(bass present, no scratchiness). Someone with access to a Book6 Pro
confirming this would be great, and I'm happy to test any patches,
topologies, or UCM profiles.
How to reproduce:
1. Boot any recent Ubuntu from a live USB on a Galaxy Book6 Pro (C910)
2. Play any music with bass, or the tone test in the attached script
3. Observe flat, bass-less, scratchy sound from the internal speakers
4. Repeat with headphones connected: sound is fine
Not affected / works:
- Headphones and headset: fine
- Windows (Dolby Atmos + Samsung processing): fine
+ ---
+ ProblemType: Bug
+ ApportVersion: 2.36.0-0ubuntu1
+ Architecture: amd64
+ AudioDevicesInUse:
+ USER PID ACCESS COMMAND
+ /dev/snd/controlC0: ubuntu 3814 F.... pipewire
+ ubuntu 3818 F.... wireplumber
+ /dev/snd/seq: ubuntu 3814 F.... pipewire
+ CasperMD5CheckResult: pass
+ CasperVersion: 26.10.2
+ CloudArchitecture: x86_64
+ CloudID: nocloud
+ CloudName: unknown
+ CloudPlatform: nocloud
+ CloudSubPlatform: seed-dir (/var/lib/cloud/seed/nocloud)
+ CurrentDesktop: ubuntu:GNOME
+ DistroRelease: Ubuntu 26.10
+ LiveMediaBuild: Ubuntu 26.10 "Stonking Stingray" - Beta amd64 (20260929)
+ MachineType: Samsung Galaxy Book6 Pro - PRHK
+ NonfreeKernelModules: zfs
+ Package: linux (not installed)
+ ProcEnviron:
+ LANG=C.UTF-8
+ PATH=(custom, no user)
+ SHELL=/bin/bash
+ TERM=xterm-256color
+ ProcFB: 0 xedrmfb
+ ProcKernelCmdLine: BOOT_IMAGE=/casper/vmlinuz --- quiet splash
+ ProcVersionSignature: Ubuntu 7.3.0-6.6-generic 7.3.0-rc4
+ StagingDrivers: intel_ipu7_isys intel_ipu7
+ Tags: stonking staging
+ Uname: Linux 7.3.0-6-generic x86_64
+ UpgradeStatus: No upgrade log present (probably fresh install)
+ UserGroups: N/A
+ _MarkForUpload: True
+ dmi.bios.date: 08/24/2026
+ dmi.bios.release: 5.39
+ dmi.bios.vendor: American Megatrends International, LLC.
+ dmi.bios.version: PRHK.3.6.61.587
+ dmi.board.asset.tag: No Asset Tag
+ dmi.board.name: NP944XJG-KG5SE
+ dmi.board.vendor: Samsung
+ dmi.board.version: SGLC204A01-C01-G001-S0003+10.0.26200
+ dmi.chassis.asset.tag: No Asset Tag
+ dmi.chassis.type: 10
+ dmi.chassis.vendor: Samsung
+ dmi.chassis.version: N/A
+ dmi.modalias:
dmi:bvnAmericanMegatrendsInternational,LLC.:bvrPRHK.3.6.61.587:bd08/24/2026:br5.39:svnSamsung:pnGalaxyBook6Pro-PRHK:pvr1.0:rvnSamsung:rnNP944XJG-KG5SE:rvrSGLC204A01-C01-G001-S0003+10.0.26200:cvnSamsung:ct10:cvrN/A:skuPRHK-940XJG-PTLH-0:pfaGalaxyBook6Pro:
+ dmi.product.family: Galaxy Book6 Pro
+ dmi.product.name: Galaxy Book6 Pro - PRHK
+ dmi.product.sku: PRHK-940XJG-PTLH-0
+ dmi.product.version: 1.0
+ dmi.sys.vendor: Samsung
** Attachment added: "AlsaInfo.txt"
https://bugs.launchpad.net/bugs/2170576/+attachment/6008829/+files/AlsaInfo.txt
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https://bugs.launchpad.net/bugs/2170576
Title:
Internal speakers sound broken (flat, no bass, scratchy/rattling) on
Samsung Galaxy Book6 Pro - CS42L45 + 2x CS35L57 SoundWire (SSID
144dc910)
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