Just bought a Macbook Pro 13 2.53GHz. The optical drive sounds awfully every time machine is started up. I have a macbook aluminum and a mac mini, both of which has a short modern zippy sound when machine starts. So I checked the machine spec and it turns out that optical drives in these machine are both branded HL-DT-ST and the crap one in new Macbook Pro 13 is Matshita UJ-868 KB19. I never expect to have this issue. Every time I turn it on at library that stupid long, loud sound kills me. Now I just find out how much I love the air with no optical drive. So the question is: Is it possible to change for another machine with HL-DT-ST drive? _______ [Update] I got this drive replaced in Apple Store. The new drive is also a Matshita UJ-868 KB19 manufactured in August 2009, but this one is very quiet and there is no weird sound anymore. Looks like the previous one is indeed a defect product. So if anyone got weird noisy sound on startup with their Matshita optical drive, don't hesitate to take your machine to Apple Store and get the drive replaced.