Services such as BBC iPlayer, Sky by Broadband and Channel 4’s 4oD use Kontiki to download the content. Kontiki seems to load and use your bandwidth, even if you are not using iPlayer, this can slow down your computer.
Use the Windows Task Manager to see if Kservice is running. The BBC has a page that explains how to stop it running on startup and when you are not using iPlayer (tinyurl.com/4h2t26). You can remove it altogether using the kclean.exe program from tinyurl.com/5msknq. However, if you do, any Kontiki-based programs such as iPlayer may not work.