Musicians Earplugs are designed to last for many years. Etymotic Research recommends that earmolds for Musicians Earplugs be made only out of silicone (not vinyl) because it does not shrink or change shape over time. Persons who lose a large amount of weight may find their earmolds no longer seal properly. In this case the earmolds need to be remade for a better fit.
My earplugs are made of silicone. My weight is stable but I have been told by a reliable source that I should change them every five years due to the evolving shape of one's ears over the years. How accurate is this rule of thumb?
(*) By musician's earplugs I mean flat-response attenuators (= frequency response that follows the shape of the natural frequency response of the open ear, but at a reduced level.)