I have a Toshiba Satellite a300 and it was originally with Vista! Two weeks ago I installed Win 7 and it seems to not detect the built-in mic!
You can see in the picture: http://tinypic.com/r/ie1jxi/6 that I have two mics! One is the default one which is the headset mic, which I am forced to use and the other one I am not sure what it is but I think it is the built-in one. It says but that it is "currently unavailable"!(and no-it sows that it is "currently unavailable" even if the headset mic is unplugged.) Can someone help me, please?