I deactivated Adblock Plus in Firefox with no noticeable improvement and i tried the same in Chrome, but the GUI still gets unresponsive. I'm running a Avast Internet Security Suite and i had problems with that AV and my VMs before. Guess what!? I deactivated the Anti Virus and everything runs flawless! The GUI got unresponsive because of my Avast Antivirus! THANKS Bonienl, i love you!