I just installed Mandrivia-2009.1 & have no sound playback as a regular user. Root user has no problem with sound.If I add "SUID" to the
permissions of the sound application or start the application as "Root" sound will play.

It appears to be a permissions problem but it might be a device identity problem too. I noticed that KDE4 "PHONON" lists different
"MUSIC" devices for Root & Regular (Non-Root) Users. Also, the Root devices will play a test sound but User devices will complain "Audio
Play Back Device HDA NVidia Does Not Work. Falling Back To Default"

Note the different warnings displayed below by the Audacious program when a sound file is played Root user & when it is played by a Regular (Non-Root) user. It seems like audacious wants a mixer called hw:0,0 but can't use it because it is reserved for the Root user by KDE PHONON sound manager.

Here is some info about my sound:

cat /proc/asound/card0/codec#0:....

Codec: Realtek ALC883


aplay -L:....

Default:CARD=NVidia
HDA NVidia, ALC883 Analog
Default Audio Device

HDA NVidia, ALC883 Digital
IEC958 (S/PDIF) Digital Audio Output

lspci | grep -i audio:....

00:05.0 Audio device: nVidia Corporation MCP61 High Definition
Audio (rev a2)

kcmshell4 kcm_phonon (RUN AS "ROOT" USER) --Output Preferences For
The "Music" Category:....

Default
hw:0,0 (ALC883 Analog)
hw:0,1 (ALC883 Digital)

kcmshell kcm_phonon (RUN AS "REGULAR" USER) --Output Preferences
ForThe "Music" Category:....

HDA NVidia () ALSA: x-phonon : CARD=0,DEV=0
HDA NVidia () #1 ALSA: plughw : CARD=0,DEV=1
default

audacious Alida_Waltz.mp3: (RUN AS "REGULAR" USER) {NO SOUND
OUTPUT}:....

** (audacious:20233): WARNING **: alsa_get_mixer(): Attaching to
mixer hw:0 failed: No such file or directory
ALSA lib confmisc.c:768parse_card) cannot find card '0'

audacious Alida_Waltz.mp3 (RUN AS "ROOT" USER) {SOUND FILE PLAYS}:....

** (audacious:20574): WARNING **: Unable to connect to dbus: Did
not receive a reply. Possible causes include:the remote
application did not send a reply, the message bus security policy
blocked the reply, the reply timeout expired, or the network
connection was broken.

Thanks for reading this post & I hope someone can help get my sound working for regular users.

A couple of random suggestions:

1. Is your regular user account part of the audio group?

2. Do regular users have permissions on /dev/dsp and /dev/mixer? If not

Thanks for your suggestions. I did play around with with Permissions, Owners & Groups & still couldn't get sound for users. However, I finally got user sound by editing my /etc/security/console.perms.d/50-mandriva.perms file. I added the following:

<sound>=/dev/dsp* /dev/snd/*
<console> 0666 <sound> 0600 root

Here are the current permissions:

/dev/dsp stan root 0666
/dev/mixer root audio 0660

I was really surprised this worked because like I sad, I tried setting permissions before without any luck.