Sound quality in calls.

Al Johnson openmoko at
Thu Sep 18 14:25:23 CEST 2008

On Thursday 18 September 2008, Armin ranjbar wrote:
> On Thu, 18 Sep 2008 10:50:03 +0100
> Al Johnson <openmoko at> wrote:
> > Thanks. This sort of question is _much_ more likely to get a useful
> > answer.
> >
> > I've not looked into this directly, but IIRC there were reports of
> > pulseaudio doing sample rate conversion on almost everything that was
> > played, munching CPU in the process and not necessarily leaving enough
> > for smooth decode of the media file. The media player in 2007.2 was
> > apparently affected by this, but if patched to use alsa directly it was
> > fine. I can't verify this as I had gstreamer errors with the mp3 I tried
> > it with. I think pulseaudio has been dropped from 2008.8 and FSO because
> > of this. I don't know what the situation is with qtopia, but if you run
> > top while playing a file you should see if anything's  hogging CPU. I
> > suggest you search the list archives for the original reports on this
> > issue as they probably contain details I've forgotten or got wrong ;-)
> >
> > mplayer by default  plays directly through alsa so isn't affected by the
> > sound server issues. That you say sound is nearly perfect in this case
> > shows the hardware limitation isn't really the issue.
> >
> > I haven't looked closely at the whole media playback issue so I don't
> > know what the best solution is. If you're lucky someone who does might
> > read this, but you may be better off reposting with a more appropriate
> > subject line.
> Already filed a bug on this :

You probably won't get much response to that bug report, first because it 
lacks sufficient detail, and second because it's against 2007.2 which is now 
more or less unsupported by Openmoko.

For improved bug reporting see the links below. I thought the policy was 
supposed to be linked from the front page of the bug tracker, but it seems 
not to be. Details like exact version numbers and the repositories the 
packages came from are important for duplicating your bug and working out why 
it doesn't happen for someone else.

2007.2 is being converted to use the FSO interfaces to make the 'Stable Hybrid 
Release' (SHR). So far there is no release image for this project, but they 
may have more ideas on this.

> the Mplayer on om2008 is directly connected to OSS not alsa, when i -ao
> alsa it becomes 'very sensible' to loads , audio stop and resumes even
> after each characters into terminals , strange ...

Have you had a look at CPU load? Is this repeatable? This is different to the 
bug report.

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