[alsa-devel] sbxfi - What works/doesn't summary

[Jason Harvey]

Takashi Iwai wrote:
> At Tue, 28 Oct 2008 17:40:40 +0000,
> Jason Harvey wrote:
>   
>> The Source wrote:
>>     
>>> You can't hear desktop sounds because they always use pulseaudio no 
>>> matter what sound system you select as default. For me pulseaudio 
>>> plays first sound fine after start, others are corrupt along with 
>>> sound from all other apps. I'll post hw_params later. Also pulseaudio 
>>> tends to crash often with this driver so I suppose your problem is the 
>>> same.
>>>       
>> Can confirm that once pulse (on FC9 at least) gets involved it sounds 
>> terrible.
>>
>> I worked out that I had removed a package pulseaudio-esound-compat at 
>> some point in the past and never realised that it contains the symlinks 
>> that gets Gnome to start the pulse server.
>> Once that was fixed the desktop effects started working but only out of 
>> my USB headset... and nothing I can find in the gui lets me do anything 
>> about it.
>>     
>
> In many cases, the pulse problem comes from the in accurate DMA position
> calculation.  PA is often too aggressively updating buffers.
>   
Thanks, I knew there was a reason I stripped pulse out of this machine 
when I installed FC9.
Is that a bug in pulse or is it something that will improve with the 
sbxfi driver?

>> mplayer and firefox/flash sound terrible, very tinny and scratchy.
>> This is with the base_rate=48000 option set in modprobe.conf
>>     
>
> Do you mean a regression with 48kHz in comparison with 96kHz?
>
>   
Sorry that was a bit ambiguous, I'd never tried 96kHz.
Have just changed base_rate to 96kHz and it performs identically to 48kHz.
Pulse mangles the sound in just the same manner at 48kHz or 96kHz.

While I was poking about in my alsa configuration I noticed that there 
is no /etc/alsa/cards/SBXFi.conf
I think pulse looks for it, get errors shown after running pulseaudio -vv
ALSA lib confmisc.c:1286:(snd_func_refer) Unable to find definition 
'cards.SBXFi.pcm.surround51.0:CARD=0'  
Would that make any difference to anything?
(Sorry if pulse issues are totally off-topic)

Regards, Jason