PulseAudio is a powerful cross-platform sound server. You can use it to directly access your audio hardware and carry the audio signals to output devices. Or because of the way it’s designed, you can use it as an a front-end for the existing, much older and mature sound servers, such as ALSA (it’s primarily an API for accessing audio drivers), OSS etc as well.
The thing about PulseAudio is that (at least in my experience) it gives you all these awesome features, but for some reason it has never worked that well for me. But ALSA on the other hand has always been an extremely stable one and has worked on all of my audio hardware devices.
Now in Ubuntu Linux, few years ago they decided to use PulseAudio as the default sound server. But since PulseAudio cannot directly communicate with the audio hardware, it still needs tools like ALSA to function. So what happens is that, after mixing the audio (on software level), PulseAudio simply ‘hands it over’ to ALSA, and ALSA takes in from there.
Anyhow, in my case, I suspect that it’s this, the bad communication between ALSA -> PulseAudio, is the reason for most of these issues, because every time I enable “audio amplification” in PulseAudio, my audio output mutes (update: This is no longer true. PulseAudio works really well under my new Dell notebook) .
Now in the past I used to use the PulseAudio Configuration window to disable this audio amplification but in Ubuntu 11.10 Pulse just enables this audio amplification automatically. So most of the time I end up no sound outputs at all.
However, out of these frustrations I just thought , “to hell with it!” (a lot of bad words were filtered :D). “I’m gonna remove PulseAudio and just use ALSA”. I just did it and now all my audio outputs works perfectly fine!.
So if you’re also having the same issue or any other similar issues with PulseAudio in Ubuntu, then perhaps you can do the same and who knows it might save your day ;-). But remember, if you remove PulseAudio, you no longer will get that pretty looking “Volume Indicator applet” anymore. And if PulseAudio is working just fine for you, then I highly recommend that you stick with it.
If you’re ready, let’s do it.
1. First let’s remove PulseAudio from your Ubuntu OS. I don’t remember since when Ubuntu used to come installed it by default, but for the recent versions such as: 12.04 Precise Pangolin, 11.10 Oneiric Ocelot, 11.04 Natty Narwhal, 10.10 and 10.04 the below command should remove it.
sudo apt-get autoremove pulseaudio
2. Now do a reboot since PulseAudio daemon (system service) is also running from the background. So it’s better to let the OS update everything.
3. Now the next time you login to your Desktop you won’t see the Volume Icon around the system tray area.
Now ALSA is installed by default in Ubuntu but since we have to have a GUI for configuring audio mixing, let’s install the default tool that used to come in Gnome desktop called: “Gnome-ALSA-Mixer” (a GTK+ front-end).
For that please use the below command.
sudo apt-get install gnome-alsamixer
4.I’m not sure whether this is really necessary but just to make sure, again reboot your PC so the configuration is updated.
5. As said before, for various reasons I have to disable the audio amplification otherwise the audio is muted. So if you too not getting any audio outputs after say running Totem for instance, then simply open your Terminal window and enter the below command.
Now this should open a new window, similar to the below one. From its window simply remove the “check” mark that says “External Amplifier”, that should solve most of your issues.
Update: If you have an amplifier, then try leaving the “External Amplifier” enabled first. If you don’t get any sounds with it enabled, then you can try disabling it (thanks ‘Chris’ for pointing it out).
Oh and make sure Master output, PCM etc aren’t muted.
Update: If you’re having issues while using ‘Gnome ALSA Mixer’, then try ‘QasMixer’, which is a new ALSA mixer GUI. It’s also known to fix some of the run-time errors of ‘Gnome ALSA …’ as well.
Well, that’s pretty much it. Now if everything goes according to plan you should hear your speakers screaming!. That’s it and good luck.