Force resolution when using Oculus DK2

Hey!

I'm using Oculus Rift DK2, Unity 4.6.3 and uWebKit in my project. I have multiple uwebkit browsers in my project.
Currently I'm suffering stuttering when all browsers are visible (fps is about 50). When I have few or one browsers visible, then there is almost no sturrering and fps is near 60.
I have tried to disable vsync and dx11, but nothing has helped.

I noticed that when I start my build application, resolution is set 2402x1461, but DK2's native resolution is 1920x1080. I was able get settings window open, when I clicked my build exe with shift down, but even though I set different resolution, the application always sets resolution to 2402x1461.

Is there some way to force lower resolution in order to improve performance?