So I also recieved the recall for the ABS O ring... They checked my car and it was fine. I have noticed and heard people here talk about a popping noise from the car when hitting bumps.. I took mine in for the recall and told my service tech about this sound.. I have told them about it before but they where never able to duplicate the occurance.. (of course) this time the did and I guess the bump stop on the Si has some problems. Some are affected, some are not.. Mine is getting serviced today!