Suddenly I cannot get to work any USB devices on my 2016 MacBook Pro with touch bar. I am using the Apple AV Adapter. I can still use the HDMI port to attach to the TV. Only the USB seems to have the problem. None of the USB devices I connect via the AV Adapter shows up in the list of devices under the USB in the hardware list. Also I don't see the USB devices light up (seems they are not being powered on) Please suggest trouble shooting steps and steps to recover.