OK, this is my MB's second trip to apple, it was bought last year July, in Oct, it was sent back for RSS (for better or worse, hope you don't know the meaning of this). this time, for two problems: 1. screen flickering 2. computer fail to detect the removal of earphone, my guess is the contact surface in the earphone jack is failing. I will report what I got from applecare in this post, update whenever I get progress. I called applecare just now, a lady took my case, the problem with this communication is: 1. I have to wait for 15 minutes (thank god i brought my phone charger with me today, otherwise I might just give up) for her to get a dispatch number! 2. She seriously told me "don't forget to package your power adapter in the box!", then I had to told her, last time I sent it back, the rep told me NOT to send power adapter. She then backed down.