"Dummy Output" No sound in Ubuntu 16.04

Solution 1:

I had a similar issue happen where suddenly (I have no idea what I updated, or what changed in the system) I could not get sound.

I did the whole pulseaudio -k && sudo alsa force-reload thing. I didn't have any cards listed from pacmd list-cards but I could see the device with commands like:
lspci -nnk | grep -A2 Audio

I even installed a newer kernel (4.8+ since it apparently has good support for my particular machine).

In the end, I rebooted into the bios and disabled the built-in audio, applied those changes, rebooted to Ubuntu, then rebooted again into the bios to re-enable the audio. Once back into Ubuntu after that, everything seemed to work great!

Don't know if this will help with other people looking for solutions to their problems. I was using a Dell XPS 13 (9350), but might be something for others to at least try.

Solution 2:

Update: I forgot you're required to have 10 points to do that. Try this.

pacmd list-cards

From there locate your audio device, and set it as the default.

An example of this would be something like

pacmd set-card-profile 2 output:analog-stereo

You can find more information on this in the following link.

Change default sound device

Unfortunatley it's difficult for me to really help you out without either some form of terminal output or a picture, a list of steps you've taken etc..

So another thing you could do is (this will make sure you get to where I tell you to go)

Open your terminal and type

unity-control-settings

That command opens the system settings. From there go to hardware section (middle) and select Sound/Sound Settings.

I'm sure you did this already, this is what I was saying before. Just to make sure we cover the basics I'll add it in again any way.

Go through each tab Output, Input (mainly those two), Sound effects, and applications. Select and set the default audio device (just click on it). You can even test the sound to verify it's there.

The reason I bring this up again is because you say it happened after you used headphones which sounds like the default device was changed.

Make sure if you're using any form of external hardware the required drivers for them are in fact installed. If you still cannot get sound, Send me a Private message with a picture or some terminal out put.

Solution 3:

Same happened to me, on Display Port, with audio from GTX 1650.

This worked for me:

pulseaudio -k && sudo alsa force-reload

upon further tests: just the pulseaudio -k alone does it, but takes 5 secs or so. I need to do this every time after waking up my PC. Ubuntu 20.04.1 LTS.

Solution 4:

working for dell +2. Mine is Dell inspiron 5570. bios->disable audio -> boot to ubuntu -> restart -> bios -> enable aduio -> boot to ubuntu