Hi there, welcome to the forums! Here is some noob advice: ALSA is updated (along with everything else) through the normal Ubuntu update process.
Originally Posted by Deadlyhydra
You can use System->Administration->Update Manager or the terminal commands:
Stick with these approved methods, and you will have a nice, stable Ubuntu system.
sudo apt-get update
sudo apt-get dist-upgrade
I would love to help you with the sound issue, but I have no idea about your hardware. The terminal command:
will tell you all about your hardware, including your audio card. (For example, mine is an Intel Corporation 82801G). You can use this information to search these forums for specific answers. Good luck!