I'm a member of vboxusers group. I installed the extension pack. When running VirtualBox as non-root, USB devices are visible but grayed-out. When running VirtualBox as root then it works fine.
How to add access to USB devices when running virtualbox as non-root?
OS: Lubuntu 12.04, VirtualBox 4.3.2r90405 with extension pack.
Best Answer
Okay, what worked for me was to use synaptic to completely uninstall (including configuration files) the commercial virtual-box 4.3 and install the virtualbox (open source edition). I then had to uncheck usb2 support, but my devices were then found (not grayed out) and I didn't need to use root either.