No sound when plugged HDMI cable.

[Edgar_Sarmento_Bezerra]

Hi.
I'm a newbie and a Ubuntu 12.04 user.
I've tried to solve the problem but I couldn't do it.
My ALSA information is located there: http://www.alsa-project.org/db/?f=ff...748303ae35b0c4
When I go to System Settings>Additional Drivers that's what appears written: "No proprietary drivers are in use on this system."

Well, hope you help me. Thanks.

[perspectoff]

I use Pulse Audio, and for HDMI I do this:

http://ubuntuguide.org/wiki/Ubuntu_R...ith_PulseAudio

In brief, I made sure that PAVU Control was installed (PulseAudioVolume):

sudo apt-get install pavucontrol

The I start PAVU Control and make sure Pulse Audio has HDMI designated:

PAVU Control -> Multimedia -> PulseAudio Volume Control -> Configuration -> Internal Audio -> Digital Stereo (HDMI) Output

There was a small quirk on my system: The HDMI cable had to already be plugged in at the time I changed the PAVU Control settings (or was it at bootup? -- I can't remember at the moment).

Then everything works ok for me. I have to switch it back if I later want to pipe the audio back through my analog (ALSA) card.

[Edgar_Sarmento_Bezerra]

I use Pulse Audio, and for HDMI I do this:

http://ubuntuguide.org/wiki/Ubuntu_R...ith_PulseAudio

In brief, I made sure that PAVU Control was installed (PulseAudioVolume):

sudo apt-get install pavucontrol

The I start PAVU Control and make sure Pulse Audio has HDMI designated:

PAVU Control -> Multimedia -> PulseAudio Volume Control -> Configuration -> Internal Audio -> Digital Stereo (HDMI) Output

There was a small quirk on my system: The HDMI cable had to already be plugged in at the time I changed the PAVU Control settings (or was it at bootup? -- I can't remember at the moment).

Then everything works ok for me. I have to switch it back if I later want to pipe the audio back through my analog (ALSA) card.

Perspectoff, I've followed each steps you said and yeah the sound has worked (I've plugged in the HDMI cable then I've changed the PAVU Control settings therefore I haven't plugged it in at boot up) however after watching the video I've wanted I've plugged off the HDMI cable and after that I've switched back the PAVU Control settings from Digital Stereo (HDMI) Output + Analog Stereo Input to Analog Stereo Input however now I have no sound neither in pc nor when I plug in the HDMI cable.
I've tried to change the PAVU Control settings to Analog Stereo Output as it is taught there http://ubuntuguide.org/wiki/Ubuntu_Raring_Hardware#HDMI_with_PulseAudio but the sound hasn't returned.
At System Settings>Sound>Output, between the options Dummy Output and Speakers Built-in Audio in the box Play sound through is selected Dummy Output.
At the PAVU Control settings>Playback in System Sounds Mono it is on Silence.
I hope this informations could help.
What should I do?

[Edgar_Sarmento_Bezerra]

Perspectoff, I've solved the problem.
I've restarted the pc with the HDMI cable plugged in then I've opened and switched the PAVU Control settings at Configurations from Analog Stereo Output to Digital Stereo (HDMI) Output and it's worked.
Before plugging off the HDMI cable I've switched back to Analog Stereo Output then I've had the sound back.
Thank you for all your help. God bless.