Recording Problem.

I have an issue. One that I really need help on. I have a Windows Vista computer, but this problem has never occurred like it has until recently.
Whenever I try to record something the microphone line is smooth, though when I try to actually say something into it or do something it begins to randomly fade in and out with loud static. Like if I push record it will go silent for a moments then hit high with a loud static pitch then go back into silence and back into static. It continues this… When doing this on the head phones and mic icon the sound spikes up all the way with each static burst…
I normally record quite often… …I can’t though until something is done with this problem…
Can anyone help me?

Please read this announcement: http://audacityteam.org/forum/viewforum.php?f=32