Dual PC Setup Audio Problem

Hey how's it going.

I started to setup my Behringer Xenyx X1204 USB today for dual pc setup and it works for the most part except that when I enable the mic on my stream pc it causes constant white noise/humming sound to enter my headphones. Also when I listen to my microphone on my gaming pc I hear a constant white noise/humming sound as well, however when I talk with my friends they say its barely noticeable. One more thing, how come the volume of the microphone on the streaming pc is much lower than the gaming pc. I have to max out a lot of the volume sliders on voicemeeter to make it similar to the gaming pc's volume.

The guide used for my audio setup: https://www.youtube.com/watch?v=P3eXz5HyB0Y

The diagram that matches the video: https://imgur.com/j6qfpRY

A picture of the mic/"line" that causes the white noise: https://imgur.com/a/eNxc3Km

Possibly useful info:

Microphone: Audio-Technica AT2035

Headphones: beyerdynamic DT 990 PRO (250 Ohm)

The Motherboard on the stream pc: ASUS Z170 PRO GAMING/AURA RGB.

The Motherboard on the gaming pc: ASUS ROG STRIX Z370-E GAMING.

Thank you.

(Original Article)