Check the brake pads, pull everything apart and clean it, make sure the wear tab on the brake pads isnt hitting the rotor. I know they are supposed to squeal but i just had this on my wifes car. It was a ticking noise, i was checking everything, suspension and bearing wise, finally i pulled off the brakes and saw that the wear tab was just barely touching the rotor in certain spots (which pointed to me as warped rotors as well) and it wa makeing the ticking sound. I replaced everything and tick was gone. Just a thought.

It could also be a wheel bearing starting to go.