After an hour on the phone to Apple support, I've been advised to take my Macbook Pro (still under warranty) to a Genius bar. My question is will they be able to fix it on site, send it away (and if so how long) or will it simply be replaced? The main fault is that the optical drive wont burn dual-layer disks but along with that the screen has several dull white blurry marks/lines that really shouldn't be present on a top of the range laptop. Oh, and my creature speakers pick up a tinny noise through the headphone socket on this laptop that they didn't from my old iMac but I understand that that isn't considered a fault. Luckily I'm going away on holiday for 3 weeks soon so it wont be missed if it's gone for repair but can I expect it gone for longer?