Shoutcast radio

Hi, i’m trying to set up shoutcast radio by using the shoutcast plugin through winamp. I get to the login info and it won’t let me change the port. The default port is 8000 when I try to erase or delete it so I can type my port number in the 8000 pops back up. So I tried to maybe type over it the so I typed my port in and the 8000 changed to 6487 or something like that which isn’t my port either. Anyone know what is going on here? How do I type my port in?