I had my car in for service for about a week. They traced the exhaust rattle and the squeak when turning the car off to a leaking exhaust flap actuator vacuum. So, they replaced the entire exhaust.
They could not duplicate the high pitched whistle noise, so they didn't do anything about it. That sound is so random and intermittent that I doubt I'll ever get it fixed.
I'll tell them again next time I take it in.