iPhone 6S not using USB3 speed/current on PC

Hello,

I have iPhone 6S connected to Windows 10 PC on USB3 port. When I view the USB device list, I see iphone connected in USB2.0 mode with 500mw current. When I connect to USB3 port on OSX on MBP, I get device listed in USB3 mode with 1600mw current. I installed latest itunes on windows but it did not fix the problem.

How do I connect iPhone 6S to PC in USB3 mode. PC supports USB 3 mode since when I connect flash drive to the same port, I see it listed as USB3.0 device using 866mw power. It is something driver/software related with iphone. Because of this charging takes much longer on windows PC then Macbook Pro, since iPhone is not using USB3.0 power mode.

Thank you in advance,

Iuri