Brake Popping Noise problems of the 2004 Jaguar XJ8

2004, Jaguar, Xj8. Vehicle had to have the brakes and transmission replaced. Also, vehicle needed a new starter because the key will not come out of the ignition. After vehicle was taken to the dealership the catalytic converter made a popping noise. There were no other problems with the vehicle to the best of the consumers knowledge. Consumer felt that the mechanics working on vehicle were guessing as to the cause of the problem without solving the problem, consumer took vehicle back to the dealer 12 times since purchasing vehicle on June 25, 2005.