I am having a somewhat similar issue since I built my Ryzen 7 3700x on a Asus X570 Motherboard.
The computer, mainly while watching videos or sometimes browsing, freezes for about 5-10 seconds intermittently. I am trying several BIOS settings to see if one of them is causing the issue.
Plus I have changed Power Plans from Ryzen to Windows.
I believe since I have Kodi running all the time that this is part of the reason for the short freezing.
When it freezes I can see my HDD LED light is solid and I keep hearing audio but the video freezes. Then when it unfreezes a few seconds later, it acts like I clicked on fast forward on the video.
I have disabled some settings via Command Prompt but so far since putting in BIOS to disable the C-States of the processor it isn't as frequent.
I have also run numerous Anti-Virus/Malware but it always comes out clean.