Connection issue

[artomos]

I sometimes go to the library and when I connect to the internet and i need to just be listening in ventrillo I cannot connect. I believe this has something to do with them having their server's IP set up in a way that Ventrillo doesnt want you in as you cannot be banned without and IP. or there could be an entirely different issue.
I can connect at home, I am not banned, and this is the same problem with all servers I have used. I am wondering if there is some way to fix this? any help is appreciated.