Krdytkyu

My volume keys are not working in xfce. When I used them it shows an indication on the screen that the volume is being changed, but the volume is not changing at all (same thing with the mute key).

The weird thing is that when I go from xfce to ubuntu the keys are now working fine.

I don't know if this matters but I have a sound card in my computer.

How can I make the volume keys work in xfce?

This is still broken in 12.10. You can fix it by installing xfce4-mixer and then manually selecting the mixers to control with it - and then going into the xfce4 settings editor and typing in the name of the "active card". The mute button still won't work properly, you can mute but not unmute the sound with it. Everything else works though, including on screen notifications. It's really tricky to get it all working, so I opened a bug: https://bugs.launchpad.net/ubuntu/+source/xfce4-mixer/+bug/1085752

In detail, in xfce4-mixer you want it to look something like this:

This should show only the primary volume control of your sound card. You have to choose a sound card at the top and then click "Select Controls..." to add controls.
Then in the xfce4-settings-editor you need to set the "active-card" like this:

Under "sound-cards" you'll see a list of every sound card for which you added mixers. You will probably have multiple cards so it might take some trial and error here to find the right one. You need to copy the name of the correct card from "sound-cards" to "active-card" - this will be the mixer which the volume buttons control.

xfce4-volumed only works for me when it is not running in daemon mode. The volume keys work for me when I run this command to kill any existing volumed processes and start a new one that is not running in daemon mode:

kill `pidof xfce4-volumed` ; mkdir -p /tmp/volumed && cd /tmp/volumed && nohup xfce4-volumed --no-daemon &

This runs the process using nohup, so the terminal in which you run this command can be closed without killing the process.

Those volume keys are gnome based... Or unity based or whatever... You have to create a custom keyboard shortcuts in the keyboard settings gui to reduce, increase and mute volume...
For volume increase, the command is "amixer set master 5%+"
for volume decrease "amixer set master 5%-"
for mute "amixer set master toggle"

I had the same problem in Xubuntu 12.04, though I don't know if it would have worked in Unity, since I only have Xfce4. In terminal, type:

$ xfconf-query -c xfce4-mixer -p /active-card -s xfconf-query -c xfce4-mixer -p /sound-card

Source: https://wiki.archlinux.org/index.php/Xfce#Xfce4-volumed

If this is a temporary problem, like it was in my case, just do it in command line:

killall xfce4-volumed && xfce4-volumed

I fixed the problem changing the "Active Card" parameter in the xfce4-settings-editor

I have two sound card (one HDMI and the other a normal one) and the selected card was different from the normal card that I was using.

I had this very odd problem as well, I could adjust the volume slider in the menu and it would do nothing. Also, if I tried adjusting it with my keyboard, the slider would move but nothing would change with the actual volume.

I fixed it by going to PulseAudio Volumne Control. In the Output Devices panel, you can see all of your sound card options. From there, I made sure the port was set to Analog Output. In your case it might be HDMI or headphones depending on where you want your sound to go. Then select the 'set as fallback option'. It looks like a green check mark.

I didn't have to install xfce4-mixer to get this to work.