15 R3, mouse click issues even after clean install

Hi,

Since  a few days my M15R3 is showing strange mouse behavior: left or right clicks are not working. The cursor is moving normally but clicks don't work at all.

The only way to fix it is to do a CTR+ALT+DEL to open the blue screen menu and then exit the screen by pressing ESC. Then the clicks are back...for a few minutes only.

I try with the mousepad and several external mouses: this is not a hardware issue since i have this with several devices.

I also did some net research and it seems that Origin launcher has some kind of overlay issue. So I stopped it and prevent automatic launch on startup : no change ! 

Therefore I thought it was a software issue and went for a clean install. Process went fine and I installed every windows and Alienware updates.

Unfortunately, I have now a clean windows... with the same clicks issue !

I have no clue...

From an hardware point of view, the laptop is in great condition: no fall, dust removed on a regular basis...

The only thing was the fact that i cannot use the speakers anymore: I used to have headphones with a 6,35 to 3,5 jack adapter. But unfortunatly the tip of the adapter broke while inserted. Therefore i have this tiny metal part stuck in the hole and the laptop now assumes that I have an headset always plugged in... thus disconnecting the speakers.

But this happened a long time ago and should not be linked to actual issue.

I really do not know what can drive the clicks crazy...

Help !