Are you running the BIOS at default, yes? No OC? If so, good.
After a fresh install of Win10, did you only use drivers off the motherboard site? I know there are newer drivers out there on tenforums for realtek. I would only download drivers from the Microsoft Update Catalog that are compatible with your hardware ID for realtek to assure you're not using something that may not be compatible.
To find hardware ID: Device manager, Sound, video, & game controllers, click Realtek HD audio, properties, click the Details tab, and in the drop down select hardware ID. You should right click it and paste it into the Microsoft update catalog search. Sort by most recent, and make sure you select the one that matches your Win10 version (Falls creator update would be for if you have that, etc). I'm on the hero alpha, my hardware ID was the 0900 one.
To verify it's compatible, click the title, then click to see what hardware ID's are compatible, yours should be in there. Try using this driver to update through Device manager and selecting this download (after it's extracted into a folder).
The intel LAN driver had a bug that caused bad audio issues. Be sure that's up to date. Get the latest online. Ignore the old one on the motherboard site. I had bad cracking/popping back when that driver was known to cause those issues.
What changed 4 months ago? Did you switch your power strip? Try another. Plug it into another outlet.
Z790 Asus Hero Maximus on 0816 BIOS (0914 and 1202 crashes for me on XMP I), Intel 13900k stock clock, Asus 4090 Strix OC edition, FF3D532G720 Teamgroup Ram running XMP I, 16gb x 2, Samsung 980 Pro 2TB x 2, Seasonic VERTEX GX 1200W, Win 11 Pro 64, Deepcool LS720 AIO, NZXT H7 Flow. Comfortably using Armoury Crate for updates/fan xpert.