webcam Logitech C920 on virtualbox guest machine

[Otacílio]

Dears

I have two guest machines on virtualbox 5.0.26:

FreeBSD xareu 10.3-RELEASE-p4 FreeBSD 10.3-RELEASE-p4 #0: Sat May 28 
09:52:35 UTC 2016 
root at amd64-builder.daemonology.net:/usr/obj/usr/src/sys/GENERIC i386

virtualbox-ose-additions-4.3.38 VirtualBox additions for FreeBSD guests

and

FreeBSD nostromo 11.0-BETA4 FreeBSD 11.0-BETA4 #0 r303759: Fri Aug  5 
02:26:47 UTC 2016 
root at releng2.nyi.freebsd.org:/usr/obj/usr/src/sys/GENERIC  amd64

virtualbox-ose-additions-5.0.26 VirtualBox additions for FreeBSD guests


On both machines when I'm using USB 3.0 xHCI for USB support and plug my 
webcam C920 I get

usb_alloc_device: Failure selecting configuration index 
0:USB_ERR_STALLED, port 1, addr 1 (ignored)
ugen0.2: <vendor 0x046d> at usbus0

and no /dev/video0

but, on both machines, when I'm using USB 2.0 EHCI for USB support and 
plug my webcam C920 I get

ugen1.2: <vendor 0x046d> at usbus1
uaudio0: <vendor 0x046d HD Pro Webcam C920, class 239/2, rev 2.00/0.11, 
addr 2> on usbus1
uaudio0: No playback.
uaudio0: Record: 32000 Hz, 2 ch, 16-bit S-LE PCM format, 2x8ms buffer.
uaudio0: Record: 24000 Hz, 2 ch, 16-bit S-LE PCM format, 2x8ms buffer.
uaudio0: Record: 16000 Hz, 2 ch, 16-bit S-LE PCM format, 2x8ms buffer.
uaudio0: No MIDI sequencer.
pcm3: <USB audio> on uaudio0
uaudio0: No HID volume keys found.


And a /dev/video0 appears


So, someone has a hint if is possible to work with USB 3.0 xHCI? USB 
pendrive works fine.


[]'s

-Otacilio