What's interesting, I cannot get my Guest to even recognize my headset if plugged into a USB 3.0 port, though it's regonized on my Host.
It's probably the drivers in my Guest OS, which the link you provided made some sense. However, I haven't a clue as to what drivers to use, as my Guest is Win 8, host has a AMD chipset, and Intel doesn't provide USB 3.0 drivers for Win 8 as it relies on Windows built-in driver.
Attached is a screenshot of my Guest USB 3.0 driver.
With all that said, I believe my headset base is USB 2.0 anyhow, though I haven't been able to confirm this.
-Scott
My setup:
Host: Win 7 x64 HP
Guest: Win 8 x64 Pro
Device: Plantronics Savi W740 Wireless headset (USB-base)
Softphone: Skype
Edit: I actually receive a Driver error message in Guest when 'connecting' my headset via VM/Removable Devices/Plantronics headset