I wouldn't bother with BMW Australia's customer care people. If the problems persist you should go straight to the people mentioned by Terry.S and with the threat of going to a TV current affairs programme. I'm sure Western Australia should also have some sort of government body that deals with consumer complaints. In NSW it's called FairTrading. If your X5 is a lemon you need to complain long and loud to everyone you can while the warranty is still in place.