Built-in mic on MacBook reacts in Sound System Prefs, but not in Skype (calls & audio settings). Can anyone help me? I can hear the person on the other side, but they can't hear me. In System Prefs, the blue bar reacts when I clap, but the same bar in Skype Audio/Video settings doesn't react. I've had this problem using Cisco WebEx as well.

In System Prefs, I selected Internal Microphone and the input volume level is up, so that can't be it.
I recently upgraded to OS X 10.6.8, and I think (not sure) it didn't used to happen before that (could be coincidence, but I thought I'd share).

I'm on a MacBook2,1.

Hope you can help :)

Sarah
Skype can select different audio input than default OSX in system preferences pane.
Have you tried going into Skype preferences and checking if you have "Internal Microphone" selected there as well?