Question / Help FPS drop/slight stutter while recording Avermedia LGX

[Typlo8]

I'm trying to record Xbox One Gameplay from my capture card (Avermedia Live Gamer Extreme) at 1080p 60fps, but the recording does not seem to turn out constant 60fps, seems to be stuttering sometimes when I look at the passing background, even though it plays perfectly on preview, and recording only uses 14-16% of my cpu.

Specs:
Intel i7 6700HQ @2.60GHz
16 GB DDR4-2133 SDRAM
Nvidia Geforce GTX 960M (4 GB GDDR5 dedicated)

Test video: https://www.youtube.com/watch?v=5Z_xLFUHPQI

What can I do to help with the fps?

 

[alincupunct]

Downscale to 720p60.

 

[Typlo8]

Hey, thanks for the reply.
I downscaled to 720p and still the same problem, I'm seeing stuttering and frame skipping. Note that the capture card works almost flawlessly on my other less powerful PC. A USB 3.0 problem perhaps? But I don't know which drivers to update for that.