This is the most stupid thing I've seen in a while...
Nahimic 3 with RX 5700XT caused tremendous amount of stuttering in my games and I wasn't able to finish GPU benchmark in userbenchmark's tests. The test wouldn't finish and my score would be 0. I tested this with 3 different drivers: 20.4.2, 20.4.1 and 20.2.2, clean install using safe mode and DDU, etc. I was also testing everything after clean Windows 10 installation and I didn't do any updates or anything between the tests.
Solution is easy, you just don't use Nahimic 3 or any audio enhancement software with this card. Maybe Nahimic conflicts with AMD's audio drivers? Who knows. Just stick to your Realtek drivers and you should be downloading them ONLY from your motherboard's manufacturer site. NEVER use programms like Driver Booster or anything similar.
How to remove Nahimic software if you use Windows 10:
Press start, write Nahimic, then RMB and click uninstall, then reboot.
What's funny the card's coil whine is way less noticeable and everything works like it should.