USB timeouts while booting

Hello freebsd-currents,

My freebsd-11 machine (r292657), whenever it boots, displays the following
repeated messages at the console:

Dec 29 09:51:14 pumpkin kernel: usbd_setup_device_desc: getting device
descriptor at addr 6 failed, USB_ERR_TIMEOUT
Dec 29 09:51:14 pumpkin kernel: usbd_setup_device_desc: getting device
descriptor at addr 6 failed, USB_ERR_TIMEOUT
Dec 29 09:51:14 pumpkin kernel: pflog0: promiscuous mode enabled
Dec 29 09:51:16 pumpkin kernel: usbd_setup_device_desc: getting device
descriptor at addr 6 failed, USB_ERR_TIMEOUT
Dec 29 09:51:24 pumpkin last message repeated 2 times
Dec 29 09:51:24 pumpkin kernel: ugen0.7: <Unknown> at usbus0
(disconnected)
Dec 29 09:51:24 pumpkin kernel: uhub_reattach_port: could not allocate
new device
Dec 29 09:51:25 pumpkin kernel: ugen0.7: <Generic> at usbus0
Dec 29 09:51:25 pumpkin kernel: umass1: <Generic Mass Storage Device,
class 0/0, rev 2.00/1.00, addr 7> on usbus0

The login prompt comes up which then gets overwritten by the output of
the process of usb being successfully recognised. I have to hit return
to get a fresh unobscured login prompt and can log in normally.

What do I have to tweak to either extend the timeout value or make the
timeout disappear?

thanks,

-- 
John