Netbook built-in mic support

I am using Trinity with Ubuntu Jaunty, an old installation. I am considering an upgrade. Before trying the latest Trinity distribution, I tried Mint 9 (Isadora). I didn't like it, it messes up too much with KDE 3. It forces me to remove KDE 3/Trinity completely if I try to install buld-essential and/or kernel source. Incredibly stupid. There is only one thing I envy about Mint: it supports the built-in microphone on my netbook, so I don't have to hold an external mic when I'm using Skype. That's new to me, it's great news, and sound quality is pretty good too! I tested the Trinity 3.5.11/Lucid and 3.5.12/Maverick live images, and the mic does not work in any of them. Do you guys know how I can achieve that with a pure "Trinity distro" installation? Thanks in advance. -- Luciano ES