I've been having a huge number of issues with both my sound and my video drivers since upgrading to Ubuntu 13.04. The problem is that my hardware is getting older, and the drivers aren't always "up to snuff" with the latest builds. I understand that hardware evolves and in order to remain current with the latest hardware, backwards compatibility isn't always on the top of everyone's priority list. I'm not mad at anyone about this, but it means that I have to take some time to both figure out what's happening and take the time and spend the money to fix it, and that sucks a little. So, to help others out who may be having the same issues I have, I'll talk a little about what I've been doing to keep up to date.
With my sound, after upgrading to Ubuntu 13.04 I had driver issues with both my SB Live and the onboard sound chip that came with my motherboard. Both would crackle and pop during VOIP conversations due to what I could only deduce as a timing issue due to lack of proper drivers.
To fix this, I needed to get a new supported sound card. I reviewed the ALSA web site and found a card that was fully supported by ALSA and I could also work with as far as affordability & quality. I chose the ASUS Xonar DS which used the fully supported AV66 chipset.
Once I received the card, however, things did not go as well as expected. Pulseaudio would not report that I had even installed the card, and still showed the previous card as being installed. I needed to "reset" Pulseaudio so that it would see my new card. To do this, I ran the following commands:
First, I removed ALSA (just in case it was reporting something incorrectly as well) and Pulseaudio and purged their configurations. This gave me a "blank slate".
$ sudo apt-get remove --purge alsa-base pulseaudio indicator-sound
Next, I needed to re-install what I just removed because, yes, I actually want to use my new sound card:
$ sudo apt-get install alsa-base pulseaudio indicator-sound
After that, we just needed to reload ALSA that's running in memory so that the new/changed modules take effect:
$ sudo alsa force-reload
After this, my shiny new card was working perfectly.
Hope this helps someone else out there!
Update for Ubuntu 14.10
I just recently had to reset pulseaudio for Ubuntu 14.10, and my tried and true article here failed me. Performing these actions in Ubuntu 14.10 no longer fully reset pulseaudio. However, after (a lot of) digging, I found the following bug report, as well as a suggestion to remove a user-specific configuration file located in the user's home directory.
$ rm -rf ~/.config/pulse
$ sudo reboot
Once you remove the user-speific config directory, logging out and logging back in (or in this case just rebooting) will get you the default configs.
I also had some trouble with my new video card's HDMI interface. For whatever reason Ubuntu would default to using the HDMI interface over my sound card, so I installed the Pulse Audio Volume Control (pavucontrol), and it allowed me to easily set my preference for my sound card via it's GUI interface.
$ sudo apt-get install pavucontrol
After making these adjustments my system was pretty happy. Hope this helps you too!
Update for Ubuntu 16.04 (quiet sound)
Just a quick update for a little change I had to make for this sound card on Ubuntu 16.04. When I did the re-install, I thankfully didn't have to do a reset like I did previously, but the sound was super-quiet, and messing with the GUI tools didn't seem to help much. What FINALLY made the significant change was updating ALSAMIXER via the command-line. Oh, command-line, how I love you so.
Basically, I just typed in the following:
Then I just used the arrow keys to modify the levels for my sound card. I set mine to 90, as I prefer to use the physical controls on the speakers directly most of the time.