Applications routed through the pulse pcm alsa-plugin crackle/die quickly
Affects | Status | Importance | Assigned to | Milestone | |
---|---|---|---|---|---|
alsa-plugins (Ubuntu) |
Fix Released
|
Undecided
|
Daniel T Chen |
Bug Description
Binary package hint: pulseaudio
I'm assuming that ubuntu-bug adds all the technical information about my system, so I'll skip on that.
In short, on Jaunty - sound from game was fine on default settings.
On Karmic - sound 'crackles' at first, and then eventually just dies. No sound coming from game at all. Checking pavucontrol, it's not emitting any sound. Nothing changed with the game. The game will also hang on exit until I kill the games output stream in pavucontrol. ("the hang on exit is caused by snd_pcm_writei hanging (gets stuck in a blocking poll in libasound)")
Now, nobody really knows what's going on, so I'll just dump all that I know at first.
The problem is somewhere in the alsa<->PA layer.
Changing the games sound buffer to be 4*4096 fixed the problem for me ("what changes is that snd_pcm_
It's affecting certain HDA Intel sound chipsets (not all HDA intel).
Mangler project says that the default latency changed: http://
There are many people on the games forum with this issue, although I can't give direct links as its in closed beta. But here are various things people have posted, that worked for some, and not for others:
http://
http://
Ubuntu forums thread regarding sound:
http://
http://
http://
http://
http://
ProblemType: Bug
Architecture: amd64
Card0.Amixer.info:
Card hw:0 'Intel'/'HDA Intel at 0xf8400000 irq 20'
Mixer name : 'Realtek ALC268'
Components : 'HDA:10ec0268,
Controls : 15
Simple ctrls : 12
Card1.Amixer.info:
Card hw:1 'Audio'
Mixer name : 'USB Mixer'
Components : 'USB047f:d955'
Controls : 4
Simple ctrls : 2
Date: Thu Nov 19 15:26:11 2009
DistroRelease: Ubuntu 9.10
InstallationMedia: Ubuntu 9.10 "Karmic Koala" - Release Candidate amd64 (20091020.3)
NonfreeKernelMo
Package: pulseaudio 1:0.9.19-0ubuntu4
ProcEnviron:
LANG=en_CA.UTF-8
SHELL=/bin/bash
ProcVersionSign
SourcePackage: pulseaudio
Uname: Linux 2.6.31-14-generic x86_64
description: | updated |
description: | updated |
affects: | alsa-lib (Ubuntu) → alsa-plugins (Ubuntu) |
summary: |
- Game that uses ALSA's sound crackles/dies quickly in Karmic + Applications routed through the pulse pcm alsa-plugin crackle/die + quickly |
The culprit was a missing, incompatible change in alsa-lib's snd_pcm_ hw_params_ choose( ) that PulseAudio relies on. Because Karmic does not ship the changesets required, you're seeing pretty horrible performance. I've uploaded a staging version of alsa-lib with these fixes to the ubuntu-audio-dev PPA. Please test and verify that it resolves the issue for you.