I am not sure what changes I made in an attempt to find out why my microphone wasn't working well, but the result of my undocumented changes is that now I have no audio at all on my Dell Vostro 3450 Laptop.

The Sound settings --> Hardware tab, which used to show an audio device, is now empty.

I tried to remove and then re-install packages that had to do with audio (pulse audio, alsa), but to no avail.

How can I get my audio back?

(I posted this question also on the Ubuntu Forums (http://ubuntuforums.org/showthread.php?p=12249713) and so far got no answer, so I am trying my luck here too. Whereever I get a solution first, I'll update the other post.)

Is your audio setting for your Ubuntu guest virtual machine set to ICH AC97?

ICH AC97 is the only VirtualBox VM audio setting which allows me to get sound when running Ubuntu as a guest and either Windows or OS X (10.6.8) as the host.

In particular, if a VM's audio setting is Intel HD Audio then sound does not work in an Ubuntu 12.04 guest.

On the other hand, sound will only work for a Windows 7 (64-bit) guest when the audio setting is Intel HD Audio. This can be rather annoying when you are working with a VM which dual boots either Ubuntu or Windows 7 as the guest OS.

I have never investigated this further to find out why it works this way or if there is a way to work around it. If you happen to find one, please let us know about it.

Note: You will have to "power off" your VM to change its audio setting.

Thanks for your answer. I am not sure why you thought I was referring to a virtual machine. This is a normal installation. In the meantime I was able to solve the problem, I am not sure exactly how, because I had tried so many things before the problem was fixed, but it was with the help of the following guide:

https://lkubuntu.wordpress.com/2011/...oubleshooting/