Bug 40632

Summary: Waking from power saving mode produces a very loud click/pop on Realtek ALC892 codec
Product: Drivers Reporter: Artem S. Tashkinov (aros)
Component: Sound(ALSA)Assignee: Jaroslav Kysela (perex)
Status: RESOLVED CODE_FIX    
Severity: low CC: alan, tiwai
Priority: P1    
Hardware: All   
OS: Linux   
Kernel Version: 3.1 Subsystem:
Regression: No Bisected commit-id:
Attachments: alsa-info.txt

Description Artem S. Tashkinov 2011-08-06 11:21:08 UTC
Created attachment 67802 [details]
alsa-info.txt

Is there a way to eliminate this problem? The click is very loud, unpleasant and it makes my HiFi speakers tremble.
Comment 1 Takashi Iwai 2011-08-08 07:33:07 UTC
This sort of problem is very specific to each h/w implementation, so it's hard to debug remotely.  Usually this happens at the time of D-state change or EAPD/pin shutdown, and putting some delays() between the transition often fixes the issue.

Does the noise appear at suspend or at resume?  Also, could you check 3.1-rc1 kernel whether the problem is still present?  We can debug easier 3.1-rc kernel.
Comment 2 Artem S. Tashkinov 2011-08-13 21:05:40 UTC
(In reply to comment #1)
> Does the noise appear at suspend or at resume?  Also, could you check 3.1-rc1
> kernel whether the problem is still present?  We can debug easier 3.1-rc
> kernel.

I'm not sure if it happens during a suspend/resume cycle, but there's a click even during the time when ALSA modules are being loaded.

3.1-rc1 kernel has the same issue.
Comment 3 Takashi Iwai 2011-08-14 09:54:52 UTC
The power-saving is a sort of suspend/resume.  Judging from your description, the pop noise comes up with the resume phase.  The fact that it even appears at the module loading time implies that the very initial power-up sequence already causes the noise.

A remaining question is whether you hear a noise at going to power-down.  Do you?
Comment 4 Artem S. Tashkinov 2011-08-25 22:09:15 UTC
(In reply to comment #3)
> A remaining question is whether you hear a noise at going to power-down.  Do
> you?

If by power-down you meant an HDA codec power down mode then yes I also hear a noise (power up sequence produces two very loud clicks, and power down sequence produces one less loud click).

I'm running 3.1-rc3.

Another problem I'd like to report is that Windows installed on the same PC is at least 2-3 times louder than Linux on maximum volume settings (and all intermediate volume settings in Linux are also 2-3 times quieter).

I guess this issue needs a different bug report, doesn't it?
Comment 5 Artem S. Tashkinov 2012-09-09 11:31:48 UTC
This bug was fixed in kernel 3.3 or even earlier, at least I cannot reproduce it any longer (on 3.5.2).