2003 Saturn Vue BRAKE LIGHTS

THE CAR RUNS FINE. THE BRAKES WORK GREAT. WHEN I AM DRIVING OR SITTING STILL THE EMERGENCY BREAK LIGHT BLINKS AND MAKES A BUZZING NOISE. IT IS RANDOM. SOMETIMES IT DOESN'T DO IT. I CHECKED AND DOUBLE CHECKED TO MAKE SURE THAT THE E-BRAKE WAS NOT INGAGED. I HAVE NOTICED THAT THE E-BRAKE DOES NOT WORK VERY WELL BUT THE NOISE IS VERY ANNOYING AND I WOULD LIKE TO KNOW WHAT THE PROBLEM IS. THANK YOU