Yeah that's the same thing I had, so in that case the white cable theory is junked!beast said:my thumb, it's completely gone
Leave it running for a bit and maybe use something like ATT to increase the fan's rpms to 100% for a while in the hope it may loosen something up?, apart from that you have to live with it or return it.
In the meantime to help take your mind off the rattle, check out this video