I had the same problem no matter if I was using IE or Firefox. Doing the following fixed it and I have never had another problem:
This issue is with your Windows Media Player settings. Close any open web browsers and open Windows Media Player. In Windows Media Player, choose Tools from the top menu. If you can not see the top menu, press the Alt key on your keyboard. This will highlight the word File and will show the other categories. Once you click on Tools, click on Options. From here, click on the network tab. You will then see four options that are checked off. When you are on this screen, please uncheck UDP. After that, click Apply and then click OK.