RE: Dell Inspiron 1525 internal microphone
I am sorry but I don't have any additional help about Webcam Center. (I have Webcam Central that has a mic icon on the Recorded Videos pane). The instructions I put in the above post for Webcam Center came years ago from a Dell moderator named Rollie, who wrote:
"Open the Dell Webcam Center, and look for Audio Source in the bottom right corner. Click on Microphone/Line In and then go to More, and select Microphone Array (SigmaTel High Definition Audio CODEC). Once the Audio Source says Microphone Array (SigmaTel High Definition Audio CODEC) then the microphone should be active."
I guess I would try approaching it from the Sound properties side. Open the recording tab of the Sound properties and if the mic array is not there then right click in the blank white area and select to show disabled and disconnected devices (in Vista or 7). If the internal mic is installed, working, and has a good connection, maybe it could be enabled that way.