I just discovered the Cheese Webcam Booth, and for all practical intents and purposes, it is perfect for what I want to do in shooting videos of myself playing my electric guitar. I am using my BOSS GT-10 effects processor as my external USB soundcard, and on my videos, my guitar comes through like a champ. My problem is this: I need for my pre-recorded backing tracks to come through in the audio on my videos, yet they are not coming through. What do I do to effect this?
You will need the pulseaudio volume control application - pavucontrol . Once you have this installed, open cheese, and the program you wish to record from (for example, rhythmbox). Begin recording a video in cheese, and set a track to play in your audio application. Leave these running and open pavucontrol from your menu (it is under sound and video as pulseaudio volume control), and click on the recording tab.
If will show you Cheese as one of your applications. Set cheese to record from the output of your system/the other program (it will appear as a sink). Now, you can stop the recording in cheese (delete it if you like) as well as the song/track in your audio player.
Now, for the rest of this session (that is, until you log out or restart), cheese will record from the other application, as opposed to your mic.