Thank you Valuvious and Rizazx! I was having this exact problem, and shutting off Network iControl seems to have fixed it, and it may have fixed a few other weird networking issues I've been having.
Guardian Fighter. I love playing the Tank in MMOs, and 4E is the first edition of D&D where you can effectively Tank in tabletop gaming. I can't wait to see how Neverwinter applies the D&D rules to an MMO.