Internal speakers not working on Acer SFN14-56 with Intel Core Ultra 5 226V on Ubuntu 26.04 LTS #6002

Problem: Internal speakers not working on Ubuntu 26.04 LTS

I am using an Acer Swift Neo SFN14-56 laptop with an Intel Core Ultra 5 226V processor. My laptop has a dual-boot configuration with Ubuntu 26.04 LTS and Windows 11.

The internal speakers work perfectly in Windows 11 on the same laptop, but they do not produce any sound in Ubuntu 26.04 LTS.

Hardware and software information

• Laptop model: Acer SFN14-56
• Processor: Intel Core Ultra 5 226V
• Operating system: Ubuntu 26.04 LTS
• Kernel version: 7.0.0-38-generic
• Audio controller: Intel Lunar Lake-M HD Audio Controller [8086:a828]
• Active kernel driver: sof-audio-pci-intel-lnl

Observed behavior

The internal speakers may appear in the graphical audio settings, but no sound is produced. The command aplay -l lists only HDMI playback devices. No internal-speaker playback device is available.

Relevant kernel log messages

The kernel log contains the following messages:

• No SoundWire machine driver found for the ACPI-reported configuration
• part id 0x6244 is not supported
• using HDA machine driver skl_hda_dsp_generic now

The SOF firmware loads and boots successfully. However, the internal audio playback device is not detected.

I also checked for the kernel module snd_soc_sn624x_sdca_sdw, but it is not present in my installed kernel.

Steps to reproduce

1. Boot Ubuntu 26.04 LTS on the Acer SFN14-56.
2. Open the audio settings and select the internal speakers if they are listed.
3. Play any audio file.
4. Observe that no sound comes from the internal speakers.
5. Run aplay -l and observe that only HDMI playback devices are listed.

Expected behavior

The internal speakers should be detected correctly and produce sound in Ubuntu, as they do in Windows 11 on the same laptop.

Actual behavior

The internal speakers do not work in Ubuntu 26.04 LTS, and ALSA lists only HDMI playback devices.

Request for investigation

Please investigate the Intel Lunar Lake audio driver, support for the SoundWire codec with part ID 0x6244, and the appropriate machine-driver configuration for the Acer SFN14-56.

Since the speakers work correctly in Windows 11, I would appreciate help identifying and resolving the Linux audio compatibility issue.