That only works if the system administrator knows what he is doing. I could bet money that the administrator at my school doesn't even know what a proxy is.
Welcome to the forums E$$3nTi4L...
Did you download the right drivers for your motherboard? Double check that you did.
Did a drivers cd come with your computer? If it did, try installing the audio drivers on that.
Hope everything works out!
Welcome to the forum medokoko!
Try checking out some threads in this section of the forums:
http://www.testmy.net/forum/index.php?board=3.0
Hope you find something that will help!