Missed your other post saying you have done this. Do you have a small child that could have put a popcorn kernel in your ear? This happened to a coworker of mine and it took him years to figure it out.

I've seen 1/4 inch to 3.5mm converters cause issues like this. Have you tried without the 3.5mm extension? Try some other source than your PC?

It seems unlikely to me that in a big bounce theory that everything would happen the exact same way - especially down to your existence + anxiety.

Are you on mushrooms or something? You should relax.