Chirp in a tribute

I have a mazda 2008 tribute. It has 14,000 miles on it. Recently, it chirps like a bird for a brief 2 or 3 seconds when the car hits exactly 45 mph. It always happens when it hits the first 45 mph and then it only happens periodically. The mechanics at the dealership are unable to pinpoint the problem.

This problem will go away as soon as the warranty expires,just wait.