[alsa-devel] intel 8x0 ALSA driver in virtualbox - choppy sound

[Takashi Iwai]

At Fri, 13 Aug 2010 17:37:33 +0100,
Lex F wrote:
> 
> Hi
> 
> Thanks for your reply. I tried to answer your questions below.
> 
> On 13 August 2010 17:06, Takashi Iwai <tiwai at suse.de> wrote:
> > We have had many problems with VMware, too :)
> > Which sound backend are you using?  Direct ALSA / dmix or PA?
> 
> I believe it's direct ALSA, I have choppy output even with
> aplay /usr/share/sounds/alsa/*.wav

It doesn't mean always that you use direct ALSA.  Try to pass -Dplughw
option to aplay.

> > Actually, there is no real interrupt, but just the virtual one,
> > thus it can be never accurate.  So, rather the question is how the
> > driver is tolerant for sloppy IRQ updates.
> >
> > Usually, when the period size is large and the buffer have many
> > periods (not two), the delayed update works more stably.
> 
> I am afraid I don't understand this :)

The comment above is rather to Jaroslav.

> I am compiling a kernel with the following options enabled:
> CONFIG_SND_PCM_XRUN_DEBUG, CONFIG_SND_VERBOSE_PROCFS,
> CONFIG_SND_DEBUG
> 
> Would any of these help to determine the cause and suggest a fix?

Fix VirtualBox :)

Or try to set xrun_debug and check kernel log as Jaroslav wrote.


Takashi