I also have the same problem, and have told AF about it. We are Mac platorm since we believe it is a better sytem, but we have a lonely PC with Windows. I don't have a problem on the PC, so I don't know if it is related to the Mac computers?
I have also tried different web browser such as Explorer, Netscape and Safari (Apple's new and very good browser).
I have another interesting problem. If I wish to receive a price online or book a ticket, I can to do when I'm on my dsl line. But if I go over my modem, I don't have any problems. I don't know why that is happen?