I recently installed VirtualBox on a Windows 8 PC with Ubuntu 13.04 as the guest. I tried to use USB, but I wasn't able to access my USB stick or my phone, it just showed up on Windows. I installed the Guest Addition and the extension pack and also added the filters. When I try to activate USB2.0 Controller, I can't start Ubuntu, it says that the deice helper structure has changed and closes. Also,I can't add me to the vboxusers group, because it doesn't exist.