HI THERE IVE JUST BOUGHT A 2001 PEUGEOT 206 A WEEK AGO AND NOW WHEN I RELEASE THE BRAKE WHEN DRIVING I CAN HEAR A HISSING NOISE COMING FROM THE FRONT PASSENGER SIDE. AS OF YET IT ISNT AFFECTING THE PERFORMANCE OF THE BRAKING BUT IT IS WORRYING AND ANNOYING ME... PLEASE DOES ANYONE HAVE ANY IDEAS OF WHAT IT IS AND HOW EASY IT IS TO FIX ?