andrewNZ: It's been shipped from Auckland to Wellington, there is a slim chance the cooler has come away from the CPU due to a jolt.
That was my thought too, but to have it happen twice is a bit odd. Honestly, I would crack it open if you are confident and have a look, make sure cooler is not obviously loose or seated wrong. From there, you can check thermal paste and CPU seating if you are a bit more confident or take one of the geekzoners up on the offer. Otherwise send it back again, but that is going to start getting expensive. You don't have much to loose though by taking a look, just make sure there are no tamper stickers or marks before opening it otherwise you may void the warranty.