MBA no Audio Input

I'm posting this in MBA becasue I've trolled the boards and it seems it belongs here.

Started with Skype, but now I think it's a hardware issue, as I can't get any 'internal microphone' INPUT on anything

from Skype to Garageband to iChat.

Am i missing somehting really simple ?

I get output through 'internal speakers' through sys prefs but no input.

I'm on 10.6.8

1.8 Ghz Intel

Thanks

JJ