usb pen drive not detecting

hi

I cant get bsd to detect any usb pen drives on my system. I have a generic 
kernel with a few extra options that i cant see causing any issues.
I do get a few kernel messages when I plug the drive in (see below). The pen 
drives are plugged directly into the usb headers on the back of the 
motherboard ie not the kvm (which works)
I'm happy to supply any extra debug information


usbd_req_re_enumerate:1539: addr=4, set address failed! (USB_ERR_TIMEOUT, 
ignored)
Root mount waiting for: usbus4
usbd_req_re_enumerate:1553: getting device descriptor at addr 4 failed, 
USB_ERR_TIMEOUT!
ugen4.4: <(null)> at usbus4 (disconnected)
uhub_reattach_port:435: could not allocate new device!

$ usbconfig
ugen2.1: <UHCI root HUB Intel> at usbus2, cfg=0 md=HOST spd=FULL (12Mbps) 
pwr=ON
ugen3.1: <UHCI root HUB Intel> at usbus3, cfg=0 md=HOST spd=FULL (12Mbps) 
pwr=ON
ugen4.1: <EHCI root HUB Intel> at usbus4, cfg=0 md=HOST spd=HIGH (480Mbps) 
pwr=ON
ugen0.1: <UHCI root HUB Intel> at usbus0, cfg=0 md=HOST spd=FULL (12Mbps) 
pwr=ON
ugen1.1: <UHCI root HUB Intel> at usbus1, cfg=0 md=HOST spd=FULL (12Mbps) 
pwr=ON
ugen4.2: <product 0x6560 vendor 0x04b4> at usbus4, cfg=0 md=HOST spd=HIGH 
(480Mbps) pwr=SAVE
ugen4.3: <USB KVM vendor 0x0d3d> at usbus4, cfg=0 md=HOST spd=LOW (1.5Mbps) 
pwr=ON

$ uname -a
FreeBSD X 8.0-BETA2 FreeBSD 8.0-BETA2 #2: Sat Jul 18 23:29:28 BST 2009 
root_at_x:/usr/obj/usr/src/sys/me  amd64


$ cat /sys/amd64/conf/me
include GENERIC


options         KDTRACE_FRAME           # Ensure frames are compiled in
options         KDTRACE_HOOKS           # Kernel DTrace hooks


options         ALTQ
options         ALTQ_CBQ
options         ALTQ_RED
options         ALTQ_RIO
options         ALTQ_HFSC
options         ALTQ_CDNR
options         ALTQ_PRIQ
options         ALTQ_NOPCC

device carp
options COM_MULTIPORT
device puc