Since I personally have friends who really can't control how loud they are without being actively conscious of it, I don't find Oobayashi strange or obnoxious. This isn't a speech problem in so much as it's really simply just a case of being easily excited. This will, in no way, impede your daily living. You get used to it pretty fast actually. Rough with migraines, but eh. There's really very little reason to be angry.