Personally I don't hear any but lots of my friends say they do. I obviously just hear silence but if you hear a ringing when there not plugged then I'd visit a doctor :D
It would be a vertebral foramen, you can always look up more info in google!
Popliteus muscle
from: https://en.m.wikipedia.org/wiki/Popliteus_muscle
The sage plant is native to the Mediterranean region.
