"You know the thickness, tolerances of wood has to be exactly right for the right tone, and volume of a soundboard has to be measured exactly, and that's done mostly by ear.

VOA: standard.2010.07.06

Recent tests found noise levels from a vuvuzela, at full volume and when pressed against your ear, equates to 127 decibels.

BBC: 10 things about the vuvuzela

It appears to be the result of the abnormal volume or composition of fluid in the inner ear.

CNN: Meniere's disease

In order for all of the sensors in the inner ear to function properly, the fluid needs to retain a certain volume, pressure and chemical composition.

CNN: Meniere's disease