Apple Broadcom BCM94360CD veeeery slow wifi

I have this card in my Hackintosh and in the beginning, I got great wifi-speeds. I have a 300/300 connection and when I test now I typically get somewhere from 5 to 25 mbit up and down. My MacBook Pro gets full speed testing from the same place.

Any idea how I can troubleshoot this?

I`ve tried to update firmware on my router, tired new channels etc, but since my Macbook gets great results, I guess the issue is my computer.