One of my 1.1.0 units is not found once connected to the USB port (windows). I've been able to upgrade the firmware up to 1.6.0 (I went version by version) using the paperclip, but shortly before the upgrade completes I can hear the sound indicating that the unit has been unmounted. Then it is not mounted anymore, so cannot configure this unit. I have the red light continuously on and the green one flashing. Any way to recover this unit?