Can't re-enable sound card from sound settings

I turned the settings for the sound card to Off (supposing I can turn it on again) but then I opened the settings selection menu and all the other options disappeared.
Is there an external software I should download ? RSVP....

I figured out how to fix it really fast, I installed PulseAudio Volume Control via Terminal sudo apt-get install pavucontrol then enabled the sound card from the pavucontrol configuration tab Hope this helps anyone that has same problem.