HTC VIVE: 4k 360degree Video causes FPS drop

I am doing 360 Degree videos with a GoPro mount. The outcome is a 4k Video which is bent around a sphere.

However, when I am starting the video within my unity project I drop to 50 FPS.
The Same Video shows just fine in whirligig.

Does anyone know how I could resolve this? Is anyone else trying around with 360° Images and Videos?

I am working with a vive too. My best bet would be this plugin: Unity Asset Store - The Best Assets for Game Making

I haven’t tested this further but the developer uses it on a vive too. You might want to try to archieve a 60fps video. 30 just dont look good on a vive.