Here is what I've tested:

• The issue occurs in both Windows 10 and Linux Mint Cinnamon.
• I tried two different 3.5 mm microphones, and both have the same problem.
• The front and rear microphone jacks both produce the same buzzing.
• I reseated the front panel HD Audio connector on the motherboard.
• The motherboard uses a Realtek ALC3220 audio codec.
• The microphone buzz is present in all recording applications.

What could have failed on the motherboard that would cause this? Could the PSU replacement have damaged the onboard audio circuit, or is there another likely cause? Are there any tests I can perform with a multimeter to determine whether the problem is the motherboard, front panel audio board, grounding, or something else?

Any troubleshooting suggestions would be appreciated.

Please help me i really need mic