HDA: Problem with sound becoming corrupted

HDA: Problem with sound becoming corrupted

[Colin Guthrie]

Hi,

I've been dealing with this issue for several months (from memory I'm
pretty sure it's affected me since 2.6.36, possibly before, but I'll
have to do some deeper digging to say for sure).

The problem is that the sound suddenly goes nuts and starts sounding
awful. It's like some buffer pointer is just a little bit out for some
reason.

I can fix the issue by closing and reopening the PCM device (as I use
PA, this is just a simple "pasuspender echo" away).

The problem is very easy to reproduce - it happens about 20+ times a day
to me - to the extent that I have added a panel launcher with the above fix.


We discussed this issue during the meeting but it seems not to be a PA
problem (my other PA devices work fine FWIW - various USB things etc,
and recording from the monitor source when the sound is odd also records
good sounds).

You can hear the sounds here (recorded via mic):
http://colin.guthr.ie/weird-sound/

And our discussion is here:
http://colin.guthr.ie/meetings/pulseaudio-meeting/2011/pulseaudio-meeting.2011-02-24-21.02.log.html#l-409

My alsa-info is here:
http://colin.guthr.ie/alsa-info.txt


This mail is really just about finding out if this is a known problem? I
know others suffer from the same problem too as I've had bug reports
confirming this.

Cheers

Col
-- 

Colin Guthrie
gmane(at)colin.guthr.ie
http://colin.guthr.ie/

Day Job:
  Tribalogic Limited [http://www.tribalogic.net/]
Open Source:
  Mageia Contributor [http://www.mageia.org/]
  PulseAudio Hacker [http://www.pulseaudio.org/]
  Trac Hacker [http://trac.edgewall.org/]

Re: HDA: Problem with sound becoming corrupted

[Jean-Yves Avenard]

Hi

On 10 March 2011 02:10, Colin Guthrie <gmane@colin.guthr.ie> wrote:
> The problem is that the sound suddenly goes nuts and starts sounding
> awful. It's like some buffer pointer is just a little bit out for some
> reason.
>
> I can fix the issue by closing and reopening the PCM device (as I use
> PA, this is just a simple "pasuspender echo" away).


>
> The problem is very easy to reproduce - it happens about 20+ times a day
> to me - to the extent that I have added a panel launcher with the above fix.

I have to raise my hand on this one too... It has puzzled me for a few
months now.
I had thought it was related to the new video/audio card I'm using a
GT220 , but this is about the same time I upgraded alsa.

Every once in a while, the audio becomes slightly distorted. Voices
sounds like they are gargling with mouthwash while talking.

Interestingly, it sounds the same for AC3 or DTS passthrough, it's
slightly corrupted, but not enough to break the AC3 stream from being
usable by the amp.

However, closing the PCM device and re-opening it doesn't fix the
issue for me ; I need to reboot.

This is seen with MythTV using ALSA directly (I wrote the audio code in MythTV)

Few MythTV users have reported it, I can't explain what is causing it..

Jean-Yves

Re: HDA: Problem with sound becoming corrupted

[Colin Guthrie]

'Twas brillig, and Jean-Yves Avenard at 10/03/11 02:41 did gyre and gimble:
> Hi
> 
> On 10 March 2011 02:10, Colin Guthrie <gmane@colin.guthr.ie> wrote:
>> The problem is that the sound suddenly goes nuts and starts sounding
>> awful. It's like some buffer pointer is just a little bit out for some
>> reason.
>>
>> I can fix the issue by closing and reopening the PCM device (as I use
>> PA, this is just a simple "pasuspender echo" away).
> 
> 
>>
>> The problem is very easy to reproduce - it happens about 20+ times a day
>> to me - to the extent that I have added a panel launcher with the above fix.
> 
> I have to raise my hand on this one too... It has puzzled me for a few
> months now.
> I had thought it was related to the new video/audio card I'm using a
> GT220 , but this is about the same time I upgraded alsa.
> 
> Every once in a while, the audio becomes slightly distorted. Voices
> sounds like they are gargling with mouthwash while talking.
> 
> Interestingly, it sounds the same for AC3 or DTS passthrough, it's
> slightly corrupted, but not enough to break the AC3 stream from being
> usable by the amp.
> 
> However, closing the PCM device and re-opening it doesn't fix the
> issue for me ; I need to reboot.
> 
> This is seen with MythTV using ALSA directly (I wrote the audio code in MythTV)
> 
> Few MythTV users have reported it, I can't explain what is causing it..

[Resend as I used the wrong email address the first time! Things have
changed since the first one tho' Jean-Yves!]

Sounds like it could be related indeed.

I've been trying an older kernel today: 2.6.36.2 with:
 Advanced Linux Sound Architecture Driver Version 1.0.23.

It worked well initially, but sadly I did get two occurrences of the
problem so far (both specifically triggered rather than happening
organically). This seems to tie in with my feeling that the problem
started off as a nuisance but has gotten significantly more problematic
with more recent kernels....

With a more recent kernel I can trigger it just changing the volume
rapidly (which triggers a "bloop" noise). With this older kernel I still
used this to trigger the problems, but it takes a while (it feels to
take a lot longer than the newer kernel). I cannot discount this being a
subjective comparison however.

I'll look further.

Col

-- 

Colin Guthrie
gmane(at)colin.guthr.ie
http://colin.guthr.ie/

Day Job:
  Tribalogic Limited [http://www.tribalogic.net/]
Open Source:
  Mageia Contributor [http://www.mageia.org/]
  PulseAudio Hacker [http://www.pulseaudio.org/]
  Trac Hacker [http://trac.edgewall.org/]