I am running Ubuntu 14.04.01 LTS desktop x64 and my sound is not working. When I first installed Ubuntu it worked fine. But, after opening up my computer and attempting to switch some components (now back to the original ones for various reasons) the sound stopped and switched to "Dummy Output".
I don't think this is a hardware plugin because it works just as it always did when I boot into Windows.
What I have already tried: - Enabling Ubuntu development sound drivers
Attempting to disable speech-dispatcher (was already disabled)
Reinstalling pulseaudio and alsa
Following the SoundTroubleshooting guide (output is http://pastebin.com/ZSke1eH1 from Step 3)