This could be a problem with your mic. I have recently experienced a similar problem. The cable on my mic had gone faulty....

or it could be the microphone jsck on your motherboard is physically damaged.

Have you tried using a connection or something to use it in a usb socket. I had a plantronics headset and mike. It had a seperate connection, which you stuck the sound and mike into. then used it to plug ionto a usb socket.

Alright guys, thanks for the suggestions, etc. I'll see what I can figure out. Thanks for all the help Mike.