yeah so basically when my car is idling there is a very high pitch frequency type noise. Its very similar to that ring tone on cell phones that hurts your ears if your younger. People 40 and up usually cant hear it because of how slow hearing loss is.
It sounds like its coming from right in the center of the engine. Pretty hard to locate in general.
I recently replaced the cars MBC (dont know brand) that came with the car with the stock hoses and retrictor pill. the noise was going on long before i put it back to stock. Currently its 100% stock idling at 18-20 vac and hitting full boost around 4000rpm