Re: Audio output heavily distorted on Xen PV dom0 if not recording (Intel ADL)

["Marek Marczykowski-Górecki" <marmarek@invisiblethingslab.com>]

[-- Attachment #1: Type: text/plain, Size: 2932 bytes --]

On Tue, May 16, 2023 at 02:02:06AM +0200, Marek Marczykowski-Górecki wrote:
> On Mon, May 15, 2023 at 06:56:22PM -0500, Pierre-Louis Bossart wrote:
> > 
> > 
> > 
> > >>> I have a rather interesting issue on HP EliteBook 1040, with Intel ADL
> > >>> HDA. Sometimes (often) audio output is heavily distorted, but then
> > >>> opening pavucontrol or just launching `parecord /dev/null` fixes the issue
> > >>> instantly. But, when the mixer or recording is closed, then few seconds
> > >>> later issue comes back.
> > >>>
> > >>> You can hear this at https://cloud.marmarek.net/s/46prqZnwrqDkBdD
> > >>> Initially recording was running, then about 10s stopped and you can
> > >>> hear the issue few seconds later. Then I starter recording again, and
> > >>> the issue is gone.
> > >>> This is how it should sound: https://youtube.com/watch?v=4Tr0otuiQuU
> > >>> I do not see any kernel messages when issue happens.
> > >>>
> > >>> The issue happens on Linux 6.1.26, 6.2.10, and 6.3.2. I haven't tested
> > >>> other versions. It happens only when running under Xen (in PV dom0). The
> > >>> very same Linux started directly works fine. Full dmesg of both native
> > >>> and Xen boots is at https://gist.github.com/marmarek/548ee79282446344a172109bcd943930
> > >>>
> > >>> When running Linux 6.3.2 there, I noticed that just after boot first
> > >>> playback is okay, but if I start and stop recording it breaks. And then
> > >>> after some time of idle it fixes itself again. I have not observed this
> > >>> behavior on 6.2.10 (it was broken initially too), but I could be also
> > >>> doing some things differently. 
> > >>>
> > >>> I have few other ADL-based systems (but not HP), and they do not show
> > >>> this issue, only this HP laptop is affected. Example dmesg from another
> > >>> ADL-based system:
> > >>> https://gist.github.com/marmarek/38c5ba3ec58f9300fbc1842ddc9fa4f5
> > 
> > >>
> > >> Could you try to switch to the legacy HD-audio driver (e.g. by passing
> > >> snd_intel_dspcfg.dsp_driver=1 option) and check whether the issue
> > >> persists or not?  This will narrow down whether it's SOF-specific
> > >> problem or not, at least.
> > > 
> > > This does help! With snd_intel_dspcfg.dsp_driver=1 the issue doesn't
> > > happen anymore, the audio output just works the whole time. But, the
> > > built-in microphone disappeared, only external (unplugged) is listed. I
> > > guess that's kind-of expected.
> > 
> > Can you check what happens with a headphone and the SOF driver?
> > 
> > The SOF driver doesn't really know/care what is on the other side of the
> > HDaudio bus, so it'd be good to rule-out an amplifier-specific
> > configuration issue.
> 
> The same happens with headphones.

Any ideas? In the meantime I tried updating alsa-sof-firmware to 2.2.5,
but it didn't help.

-- 
Best Regards,
Marek Marczykowski-Górecki
Invisible Things Lab

[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 488 bytes --]