I have a base 2005 pontiac grand prix, with new front and back brake pads, and rotors. I have also recently replaced my front bearings. I have noticed that when i drive for longer periods of time 15+ minutes that my car starts to make a very high pitched squeal/chirp sound. Sometimes it remains constant other times it comes and goes. The only thing that makes the noise stop is to apply my brakes (unless it randomly decides to stop on its own) I can't pinpoint where exactly the sound is coming from, and i've had several people take a look at my car and they can't figure out what could be causing the noise, they've primarily taken apart everything to do with my wheels and brakes. Any ideas as to what i should have looked at next would be amazing!!!