Hyperacusis is the brain saying "Hey this noise hurts or is too loud." In order to get rid of that and teach your brain that noise isn't painful is to expose yourself to everyday noises. There will be some pain as you start to do this. Don't over do it and work your way up to what you can handle volume wise. Don't use earplugs unless it's a loud noise like lawnmowers. Earplugs makes hyperacusis worse.