[CentOS] Flaky desktop audio behavior.

Wed Jul 9 16:07:00 UTC 2008
William L. Maltby <CentOS4Bill at triad.rr.com>

On Mon, 2008-07-07 at 09:13 -0700, nate wrote:
> William L. Maltby wrote:
> 
> > I feel it might be related to Jim's problem. I feel it might be a bug.
> >
> > Can anybody reproduce? I think the T'bird step is coincidental. I think
> > any sound played as another user should reproduce it. Hmmm ... I might
> > be assuming to much if I assume another user is significant.
> >
> 
> I don't see why the desktop owner would be the only one that can play
> a sound. But in any case have you checked to see if the sound device
> is locked by another process? When I have sound issues I usually run
> lsof | grep /dev/dsp to see what, if anything is using the sound card

That returned nothing. So I ran it w/o the dsp and manually extracted
anything interesting. Got just these, which look normal.

mixer_app 10922 hardtolove    2u      CHR        1,3
1604 /dev/null
escd      10926 hardtolove    0r      CHR        1,3
1604 /dev/null

A ps yielded (501 = hardtolove) the below. The user that ran the T'bird,
which trumpeted mail arrival, was 502.

501      10906     1  0 07:35 ?  00:00:00 gnome-volume-manager
--sm-client -id default5
501      10922     1  0 07:35 ?  00:00:00 /usr/libexec/mixer_applet2
--oaf -activate-iid=OAFIID:GNOME_MixerApplet_Factory --oaf-ior-fd=20
501      10926     1  0 07:35 ?  00:00:00 ./escd
--key_Inserted="/usr/bin/ esc" --on_Signal="/usr/bin/esc"

Again, looking normal to me. That is *if* they should still be active,
which I assume is the case.

Looking to reduce the scope of investigation (or conversely expand it
beyond 5.2 a tad) I had booted this session with the previous (5.1)
kernel. And experienced the same problem. So it seems to not be 5.2
kernel related. This would seem to indicate that it is X/Gnome related
across 5.1 and 5.2 versions of libraries/applications.

A diff of the /proc/asound/ file contents from a previous normal
situation with the contents after this problem was replicated shows only
the kernel for significant differences.

432c432
< Kernel: Linux centos501.homegroannetworking 2.6.18-92.1.6.el5 #1 SMP
Wed Jun 25 13:49:24 EDT 2008 i686
---
> Kernel: Linux centos501.homegroannetworking 2.6.18-92.1.1.el5 #1 SMP
Sat Jun 21 19:04:27 EDT 2008 i686

Slowly continuing investigation as opportunities arise...



> and kill it. To me it sounds like thunderbird from the other user is
> accessing the sound card directly, perhaps preventing other apps from
> accessing it. Some desktop setups include a sound daemon like esd or

Clarification: the "other user" is me on the desktop, su'd to another
user in gnome-terminal and "nohup thunderbird&".

Since *real* id, as opposed to *effective* id, may have effect here, I
though I should mention it. Having done programming in many languages
over an extended time, and having seen the general level of competence
and attention to detail (the old 80/20 rule seem to apply), I don't
trust them to do it right all that consistently.

> karts(?), to facilitate multiple things accessing the sound card
> simultaneously, but I'm not sure what their capabilities/limitations
> are as I rarely if ever use them.
> 
> nate
> <snip sig stuff>

-- 
Bill