Audio

John Morales: To play and capture sound, it comes down to selecting the right device on your system. A useful command for querying all the ALSA devices:
$ sudo alsactl names

This will create a file /etc/asound.names. (Must be run as root, so this won't work on CLIC.) The asound.names file has a "pcm" section that shows all alsa-registered devices/names. (e.g., "plughw:0,0", "plughw:1,0", et al). You'll want to look at the device descriptions and play around with using each of the names until you find the right one.

At first i thought you always use "default", but it actually depends. In my case, i'm using a USB headset, so they're registered as a new alsa device whenever they're plugged in. This means that the device number varies depending whether they're plugged into the machine before or after booting up. (for me, plugged in before boot and they're plughw:1,0. Plugged in after system is up and they're plughw:2,0)

if you don't have a USB headset, then it could be that the playback and capture device names of your sound card are separate, so maybe you can't use the same name for both.