[alsa-devel] PROBLEM: snd_intel_hda audio regression in 2.6.36-rc5
tiwai at suse.de
Wed Sep 22 16:40:24 CEST 2010
At Wed, 22 Sep 2010 17:28:15 +0300,
Aki Parviainen wrote:
> On Wed, Sep 22, 2010 at 12:31 PM, Takashi Iwai <tiwai at suse.de> wrote:
> > At Tue, 21 Sep 2010 20:32:54 +0300,
> > Aki Parviainen wrote:
> > >
> > > I've noticed an audio related problem in 2.6.36-rc5: when using
> > 2.6.36-rc5 kernel
> > > I don't get normal two channel PCM audio at all on my machine, however
> > multichannel audio
> > > works just fine.
> > What does this mean exactly? Could you show your test method?
> Thank you for your answer and sorry for being unclear! This means that
> whenever I try to output regular stereo audio from files or DVB for example
> I cannot hear anything at all with 2.6.36-rcX kernels. Before 2.6.36-rcX
> kernels normal stereo audio works just fine. However with 2.6.36-rcX kernels
> and all the previous kernels digital preencoded (like Dolby Digital, DTS)
> audio works just fine. I am using Kaffeine 1.0 and VLC 1.1 (both from Debian
> unstable) to play audio, both programs work exactly the same. My test method
> is basicly this:
> -boot with 2.6.36-rc4 or 2.6.36-rc5
> -open kaffeine or vlc
> -start playing mp3 file -> nothing comes to the amplifier
> -start playing mkv file with 5.1 track -> correct audio comes to the
So, you are testing only over SPDIF output, right?
> > > I'm using snd_hda_intel and I've configured ALSA to send all
> > > audio to spdif output. With earlier kernel versions this kind of setup
> > works
> > > just fine but with 2.6.36-rc5 only audio that works is digital preencoded
> > audio (5.1 dolby digital from
> > > dvd:s / mkv:s) works. There's no errors or anything but nothing comes to
> > my
> > > amplifier. I've also tested 2.6.36-rc4 and it has the same problem, in
> > the past I've never had any audio problems with mainline kernels.
> > Which kernel did it work?
> 22.214.171.124 and every earlier kernel tested. Unfortunately the first 2.6.36
> based kernel that I tested was 2.6.36-rc4 and there audio doesn't work
> > > Booting with earlier kernel solves the problem immediately.
> > Run alsa-info.sh (with --no-upload option) on both working and
> > non-working kernel, and attach two files for compare. This will give
> > a more clear sight what is different between them.
> Here's the alsa-info files attached from 126.96.36.199 (works) and 2.6.36-rc5
> (doesn't work).
Looks like the SPDIF status bits has been reset by some reason.
Try to restore via iecset program included in alsa-utils package,
iecset original on
iecset category 0x02
If this doesn't help, try to unload sound driver once, remove (or
backup) /etc/asound.state (which might be in a different path
depending on the distro), then load sound modules again.
This will restore the default SPDIF status. Unmute / adjust mixer
setups appropriately after doing this.
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