[alsa-devel] Bugs on aspire one A150

[Takashi Iwai]

At Mon, 16 Mar 2009 13:03:12 +0100,
Andreas Mohr wrote:
> 
> Hi,
> 
> On Sun, Mar 15, 2009 at 10:21:17AM +0100, Andreas Mohr wrote:
> > Hi,
> > 
> > On Mon, Nov 24, 2008 at 03:35:10PM +0100, Takashi Iwai wrote:
> > > At Sat, 22 Nov 2008 21:00:18 +0200,
> > > Maxim Levitsky wrote:
> > > > Finally, I found how to reproduce that bug,
> > > > I mean to get normal volume on internal mic, I have to increase volume
> > > > only on left or right channel.
> > > > 
> > > > So, this happens always, and _only_ when recording _mono_ sound from internal
> > > > mic.
> > > > 
> > > > Since hardware doesn't support hardware mono input, tested with -D hw:0
> > > > I suspect this to be alsa-lib bug, any ideas?
> > > > Happens with arecord -D plughw:0 -c1 .
> > > 
> > > What does show with -v option?
> > 
> > OK, I could fully reproduce this now (sorry for the delay!).
> > 
> > Currently 2.6.28, u8.10, model acer-aspire, libasound2 1.0.17a-0ubuntu4,
> > libasound2-plugins 1.0.17-0ubuntu5.
> 
> Same microphone behaviour on 2.6.29-rc8 (additionally remembered to enable
> CONFIG_SND_HDA_HWDEP for further testing!), u9.04, model acer-aspire,
> libasound2 1.0.18-1ubuntu7, libasound2-plugins 1.0.18-1ubuntu4
> (yes, I've just done some monster upgrade).
> 
> Will try to eventually analyze things using your _HWDEP-related tools.

The question in the top priority is whether it's a kernel driver
issue or alsa-lib converter issue.  Could you check whether the sounds
recorded with -Dhw (and with matching rate, format, etc) have the same
noise problem at first?

And, if it's about the alsa-lib conversion problem, we can reproduce
without the hardware, e.g. via file plugin...


thanks,

Takashi