[pulseaudio-discuss] Stuttering sound with SDL apps

[Colin Guthrie]

Colin Guthrie wrote:
> CJ van den Berg wrote:
>> I don't know about SDL, but ALSA definitely has the same problem on
>> Debian. It seems, from reading the plug-in code, that the ALSA plug-in
>> drops the connection on every buffer under run. I don't know what the
>> purpose of that is supposed to be. It doesn't make much sense to me.
>>
>> As a workaround, you can raise the minimum period size in the ALSA
>> plug-in. That prevents the stuttering in Skype and Ekiga, but doesn't
>> really fix the problem. It only makes it less likely.
>>
>> The strange thing is though that Skype still creates thousands of
>> connections even with a larger period size (and no stuttering), so there
>> must be other reasons for the plug-in to drop the connection too, or I'm
>> missing something somewhere. Hmm, come to think of it, perhaps I only
>> raised the period size for the sink and not the source...
> 
> Thanks for the info CJ, I'll maybe have to learn some slightly in depth
> pulse/sound stuff at some point and actually look into the API calls in
> SDL and see if I can come up with a little patch for it.

The default buffer attributes seem to be a little ill thought out. I've
just reverted them to the defaults and it seems to work OK for the test
cases I tried although I'm waiting for more feedback from others.

If anyone with more knowledge than me cares to work out better defaults
I'm happy to try them.

Patch:
http://svn.mandriva.com/cgi-bin/viewvc.cgi/packages/cooker/SDL12/current/SOURCES/SDL-1.2.13-pulseaudio-default-buffering.patch?view=markup

Source to which it applies:
http://www.libsdl.org/cgi/viewvc.cgi/branches/SDL-1.2/src/audio/pulse/SDL_pulseaudio.c?view=markup

Col