At least I think it's the hard drive. The problem is intermittent and varies in severity. Here is a recording (recorded with Audacity) using the built in mic while the laptop is in clamshell mode. here is a recording of what it sounds like normally for comparison This is normal: http://rapidshare.com/files/20771164/normal.mp3.html and Here is the weird noise: http://rapidshare.com/files/20770816/uhoh.mp3.html Is my hard drive dieing? Will Apple replace my hard drive for free if I bought the MBP refurbished back around October 06?