I had this problem at around the same mileage you do. I talked to two dealerships and they said that since they're high friction brakes, if you don't use them to their full potential a light film can build on the rotor. They said to take the car out on the freeway or open road and when safe, do a really quick run to 0-80 or 100 then slow the car really quickly, not screeching tires quick but decently quick. When you do this, its supposed to help burn off the film. I did this on an open road 3-4 times (brought the car up to 80, then slowed really quick down to 40 and brought it back up to 100 and did the same thing) and it stopped the squeaking