[alsa-devel] Constant noise on HDA ALC275

Julien Danjou julien at danjou.info
Fri Nov 2 12:29:40 CET 2012

On Fri, Nov 02 2012, Takashi Iwai wrote:

>> I just did that using the hda-analyzer tool. I changed 0x14 to uses 0x0c
>> as a source, and it's indeed much better. The noise disappear when
>> neither master or speaker is muted, and actually the music playback
>> sounds better and without the little background noise I still hear on
>> low volume level.
> Good to hear.  What's the remaining issue?

Well, it's still not perfect, and as I wrote, if any of "master" or
"speaker" is muted, the noise kicks back in instantly. :(

> The current parser prefers the line-out as the primary output over the
> headphone.  Then it tries to assign from the smaller NID, so 0x0c is
> assigned to the line-out (which is the speaker in your case), then
> 0x0d is to the headphone.

Ok, thanks for the explanation.

>> I'm still trying to find a way to fix the noise when speaker or master
>> are muted. No chance so far. :(
> Do you mean that the noise is there with rerouting like the above, or
> you are asking for a patch to achieve the rerouting?

If "master" or "speaker" is muted, the noise kicks back in, whatever the
routing is.

At this point, I wonder if it wouldn't be simpler to just boot the
machine under Windows and dump the HDA state to see how the Windows
driver set up all the routing. Do you think this kind of approach would
work, and in that case, is there a tool do achieve that?

Julien Danjou
# Free Software hacker & freelance
# http://julien.danjou.info
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: application/pgp-signature
Size: 835 bytes
Desc: not available
URL: <http://mailman.alsa-project.org/pipermail/alsa-devel/attachments/20121102/95e00fe8/attachment.sig>

More information about the Alsa-devel mailing list