Advertised in this month's Science Focus - no view as to whether it's a good idea or not, but upgrading your ears is a new one on me...
www.flareaudio.com

Calmer® | An Alternative To Traditional Earplugs
An earplug alternative to reduce stress and calm your everyday sound. Soothe sound sensitivities and noise related stress. Perfect for sensitive hearing, autism, hyperacusis, misophonia and other sensory processing conditions.
