GDM Greeter Sound

Question

OK I don't know if this is the right forum for this, but I am a newbie so here goes..
I use gnome and in the greeter I go to the setup screen (Actions --> Configure the Login Manager).  Under the Accessibility tab there is a checkbox 'Make a sound when login window is ready' which is checked by default and I hear a beep through the PC Speaker.  Underneath the checkbox is a browse button to choose a sound file.. so I choose a .wav file from /opt/gnome/share/sounds but it won't play.. I still get the PC Speaker beep.
So I CTRL-ALT-F1 for terminal and do a 'ps -Af to see that /opt/gnome/libexec/gdmgreeter is being run by user 'nobody'
gpasswd -a nobody audio
still no luck..
Thanks in advance for any suggestions
P.S.  If you run gnome and want to see what I'm talking about without log out, go to Applications --> System Tools --> New Login in a Nested Window
Very handy

Answer 1

Hi and welcome to the club!
This is the original;
/opt/gnome/share/gdm/defaults.conf
Put your customisations here.
/opt/gnome/etc/gdm/custom.conf
This is what i have to play sound from gdm.
in sectiond [daemon]
SoundProgram=/usr/bin/play
in section [greeter]
# If SoundOnLogin is true, then the greeter will beep when login is ready for
# user input. If SoundOnLogin is a file and the greeter finds the 'play'
# executable (see daemon/SoundProgram) it will play that file instead of just
# beeping.
SoundOnLogin=true
SoundOnLoginFile=
# If SoundOnLoginSuccess, then the greeter will play a sound (as above) when a
# user successfully logs in.
SoundOnLoginSuccess=true
SoundOnLoginSuccessFile=
# If SoundOnLoginFailure, then the greeter will play a sound (as above) when a
# user fails to log in.
#SoundOnLoginFailure=false
#SoundOnLoginFailureFile=
Also you will have to install 'sox' to play audio with /usr/bin/play , _and_ you will have to restart gdm / or reboot your computer to load the changes.