Update: found a reproducible trigger, captured the failed state, and re- verified the cure.
Trigger: a warm reboot round-trip through Windows (dual-boot machine: warm-restart to Windows, use the microphone there, warm-restart back to Ubuntu) brings the microphone up in the corrupted state — full-scale impulse train, 3953 large sample-to-sample discontinuities in the attached ~5.8 s capture. Reproduced deliberately on the first attempt; will re-verify repeatability. Cure verified in the same cycle: clean state confirmed → Windows round- trip → corruption confirmed and logged → cold power-off → clean capture confirmed. This matches all earlier persistence findings (the corrupted state survives warm reboots, suspend/resume, and a full SOF/SoundWire/codec module reload; only cold power-off clears it). Interpretation: Windows' audio driver leaves the SoundWire codec/link in a state that the Linux stack does not fully re-initialize on warm boot. Since this machine is Ubuntu-certified and dual-boot is a common configuration, this seems squarely in scope. Attaching: alsa-info captured in the failed state, full dmesg of the affected boot (no sof/soundwire errors logged — the corruption is silent), and the corrupted capture sample. ** Attachment added: "Archive.zip" https://bugs.launchpad.net/ubuntu/+source/linux-hwe-6.14/+bug/2160386/+attachment/5981173/+files/Archive.zip -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/2160386 Title: Dell Precision 5690 (Ubuntu-certified, MTL): internal DMIC capture corrupts to full-scale impulse train; state survives warm reboot, cleared only by cold power-off To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux-hwe-6.14/+bug/2160386/+subscriptions -- ubuntu-bugs mailing list [email protected] https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
