Crackling sound in games, pulseaudio CPU usage high (F10)

[NM]

On Mon, 01 Dec 2008 17:04:14 +0100, Nigel Henry wrote:

> Do you have the same sound problems when playing an audio cd, or playing
> music files (.ogg, .mp3)?

Nope, no such problem.

> If it is Pulseaudio causing the problem, and you don't use it for
> anything specific, you could just disable it by removing the package
> alsa-plugins-pulseaudio. If you are using KDE like me, this will also
> remove the package kde-settings-pulseaudio. By doing this your audio
> apps will revert to using Alsa directly. If any of the games you play
> use SDL, you will need to add the following line to /home/<user>/.bashrc
> , which will remove the hack that SDL programs need to use Pulseaudio.
> 
> unset SDL_AUDIODRIVER

Thanks for the tip.

>> This is my sound card:
>>
>> 00:1b.0 Audio device: Intel Corporation 82801I (ICH9 Family) HD Audio
>> Controller (rev 02)
>>
>> [root at ws log]# grep -i hda dmesg
>> HDA Intel 0000:00:1b.0: PCI INT A -> GSI 22 (level, low) -> IRQ 22 HDA
>> Intel 0000:00:1b.0: setting latency timer to 64 hda_codec: Unknown
>> model for ALC883, trying auto-probe from BIOS... ALSA
>> sound/pci/hda/hda_codec.c:3021: autoconfig: line_outs=4
>> (0x14/0x15/0x16/0x17/0x0)
>> ALSA sound/pci/hda/hda_codec.c:3025:    speaker_outs=0
>> (0x0/0x0/0x0/0x0/0x0)
>> ALSA sound/pci/hda/hda_codec.c:3029:    hp_outs=1
>> (0x1b/0x0/0x0/0x0/0x0) ALSA sound/pci/hda/hda_codec.c:3030:    mono:
>> mono_out=0x0 ALSA sound/pci/hda/hda_codec.c:3038:    inputs: mic=0x18,
>> fmic=0x19, line=0x1a, fline=0x0, cd=0x0, aux=0x0
> 
> What is the make and model of your Laptop/PC ?

It's home-made with an Asus motherboard. I'll post the details when I get 
back home.

> 
> Can you post the output from the following commands.
> 
> cat /proc/asound/version

Advanced Linux Sound Architecture Driver Version 1.0.17.

> grep ^Codec /proc/asound/card?/codec* /sbin/lspci -vn             (just
> the bit for the soundcard)

Codec: Realtek ALC883

00:1b.0 0403: 8086:293e (rev 02)
	Subsystem: 1043:8277
	Flags: bus master, fast devsel, latency 0, IRQ 22
	Memory at f9ff8000 (64-bit, non-prefetchable) [size=16K]
	Capabilities: [50] Power Management version 2
	Capabilities: [60] Message Signalled Interrupts: Mask- 64bit+ 
Count=1/1 Enable-
	Capabilities: [70] Express Root Complex Integrated Endpoint, MSI 
00
	Capabilities: [100] Virtual Channel <?>
	Capabilities: [130] Root Complex Link <?>
	Kernel driver in use: HDA Intel
	Kernel modules: snd-hda-intel


> Did the sound just work ok post install of F10, or did you have to set
> model options for snd-hda-intel?

Didn't set anything. 

Sounds works ok without PA (used to run under Ubuntu w/o PA)

> There are a whole bunch of model options for the ALC883 codec, some of
> which may give you more sliders/controls in alsamixer, when run as user
> in a terminal. To see all the controls when pulseaudio is enabled, you
> will have to open alsamixer as below, otherwise you will only see one
> control for pulseaudio.
> 
> alsamixer -D hw:0
> 
> Crackling sounds can be a problem to resolve. I know that pulseaudio can
> be responsible for low volume output, and if you are having to push the
> volume up to 100% to get decent sound levels to your speakers, it could
> be that the card is being pushed beyong it's capabilities. It's
> interesting that when you don't use pulseaudio, the sound is ok.
> 
> I'll give you a list of model options when you post back, but I need to
> know the alsa driver version, that's on F10 first.
> 
> All the best.
> 
> Nigel.

Thanks for your help.

One other problem I notice with PA is that sometimes the sound sounds 
saturated, as if it was compressed up and then scaled back down. I have 
this problem after playing around with various volume settings (either pa-
volume or alsamixer etc)

The main problem here is the CPU usage, which is strange. Any idea what 
causes this?