"@JL, thanks, I will check it! "

"JL, do you think it can affect also the stability of the drone in manual mode?
I had an issue last sunday, not able to keep stable the QN and it lead to some damage on the quad... I did sensor calibration then but I need to test next weeked, if…"

"Found the issue, is in the connection between internal micro USB to external mini USB.
I did some checks as Cedrick suggest (thanks for the tips!) but seems there are a short circuit on this bracket cable/connectors... need to redo it completely.…"

"... one quastion for those who open the Quanum: the lower USB port is a prolongued of the internal one? Maybe I just can bypass it and go directly to the internal one as per J.L pictures..."

"Thanks Cedrik!
I was thinking the same, maybe a 'cold' soldering?
I will then open the drone in the next days and check all them... 
BTW, I add that I connect yesterday my RoBo 3D printer that use the same Arduino device and with the last driver…"

"Hello to all! 
Thanks to the J.L. indications I did bought a Quanum Nova from HK that arrived this week and I already start to test the Mission Planner.
Now I have an issue that I not know if is connected to the quad or to the PC (Windows 7): I…"