Alienware 15 R2: Video not working on external display

Hi,

I've got a Alienware 15 R2 with a NVIDIA GTX 970M and a Dell Monitor (SE2417HG). They are connected using a HDMI cable.

Videos from Windows 10 apps like Netflix of TMN Go aren’t shown when they are displayed on the external monitor, but they are displayed on the laptop screen. I’ve tried with the latest NVIDIA driver from Dell support web page (10.18.13.5940) and from NVIDIA web site (372.70).

Is there a video setting or configuration that I’m missing?

Thanks!