What is the root of the "no sound" problem for some programs?

[Paul Johnson]

I'm running F8 with KDE. I upgraded from F7.  system-config-soundcard
plays a sound.

When the system starts, I see this in a popup:

Informational- artsmessage

Sound server informational message:
Error while initializing the sound driver:
device: default can't be opened for playback (Connection refused)
The sound server will continue, using the null output device.

I am able to hear audio in flash movies played inside firefox and i
CAN play songs in Amarok.  But if I try to view the same videos after
downloading them, mplayer says

*** PULSEAUDIO: Unable to connect: Connection refused
[AO_ALSA] Playback open error: Connection refused
Could not open/initialize audio device -> no sound.
Audio: no sound
Starting playback...

I've been searching the net and find about 1000 posts on this same
problem. It appears to be deep in the guts of Ubuntu and Fedora, users
in both lists are posting suggestions like crazy.

On the surface, the most logical approach is to look at this as a
console permission problem.

Permissions on /dev/dsp were 660, so maybe I need to follow the advice
Ubuntu users follow of making it 666 (either manually or by adding 2
lines in /etc/security/console.perms.d/50-default.perms. Note the new
sound lines at the end of each stanza:

<pilot>=/dev/pilot
<scanner>=/dev/scanner* /dev/usb/scanner*
<rio500>=/dev/usb/rio500
<fb>=/dev/fb /dev/fb[0-9]* \
     /dev/fb/*
<kbd>=/dev/kbd
<joystick>=/dev/js[0-9]*
<gpm>=/dev/gpmctl
<dri>=/dev/nvidia* /dev/3dfx* /dev/dri/card*
<mainboard>=/dev/apm_bios
<pmu>=/dev/pmu
<bluetooth>=/dev/rfcomm*
<irda>=/dev/ircomm*
<dvb>=/dev/dvb/adapter*/*
<sound>=/dev/dsp* /dev/snd/*

# permission definitions
<console>  0600 <pilot>      0660 root.uucp
<console>  0660 <scanner>    0660 root.lp
<console>  0600 <fb>         0600 root
<console>  0600 <kbd>        0600 root
<console>  0600 <joystick>   0600 root
<console>  0700 <gpm>        0700 root
<console>  0600 <mainboard>  0600 root
<console>  0600 <rio500>     0600 root
<console>  0600 <pmu>        0600 root
<console>  0600 <bluetooth>  0600 root
<console>  0600 <irda>       0600 root
<console>  0600 <dvb>        0600 root
<xconsole> 0600 /dev/console 0600 root.root
<console>  0600 <dri>        0600 root
<console> 0666 <sound> 0600 root

Still after that, sound signals were refused.  I don't have a sound
group on my F8 system, perhaps I should change <sound> to <pulse> ???.
 Changes like that did help about 3 years ago in Fedora 5, as I
recall, when I needed to allow users to play cdroms.  But the pulse
audio problem is deeper, it appears to me.

Many people say "turn on services ConsoleKit and Avahi."   I did have
ConsoleKit on already.  I had turned off avahi.   Its help information
says you should only turn it on if you are on a network using Zeroconf
service discovery, and I'm not.  If avahi is really required, that
message about the module that appears in system-config-services
urgently needs fixing.

Some people say remove the rpm

alsa-plugins-pulseaudio

and another Fedora 8 person has urged me to install

kde-settings-pulse

One person told me that if I upgraded from FC7 to F8, then existing
users inherit some kind of configuration mistake/error and they can't
be put right unless you clear out some dot files, but nobody seems to
be quite sure what file that might be.

None of these are working for me yet, but I've followed down so many
blind alleys there's no telling what unneeded changes I made or what
mistakes I imposed.

Usually, when there is some widespread problem like this, there are
lots of little half-baked fixes floating about, and eventually
somebody who really understands the root of the problem fixes an RPM
in the distribution somewhere and the problem goes away.  Problems
like "no video after suspend" or "ide cdrom not found" seem to end up
disappearing and it is not so easy to figure out why.

Concerning the sound problem, does anybody know what the real root of
the problem is?

PJ

ps: is this informative?

$ rpm -qa | grep pulse
pulseaudio-libs-glib2-0.9.8-5.fc8
pulseaudio-libs-zeroconf-0.9.8-5.fc8
pulseaudio-utils-0.9.8-5.fc8
pulseaudio-libs-0.9.8-5.fc8
alsa-plugins-pulseaudio-1.0.15-2.fc8
akode-pulseaudio-2.0.1-9.fc8
gstreamer-plugins-pulse-0.9.5-0.4.svn20070924.fc8
pulseaudio-core-libs-0.9.8-5.fc8
kde-settings-pulseaudio-3.5-36.fc8.1
pulseaudio-0.9.8-5.fc8
pulseaudio-module-x11-0.9.8-5.fc8
pulseaudio-libs-0.9.8-5.fc8

$ alsacard
*** PULSEAUDIO: Unable to connect: Connection refused
Open error: Connection refused
0


-- 
Paul E. Johnson
Professor, Political Science
1541 Lilac Lane, Room 504
University of Kansas