Hi Matthew,
I recommend speaking to the person who you purchased it from first. If they can't help, then speak directly to Corsair.
The grinding noise your speaking of is usually the bearing inside the fan itself, many fans of different brands can experience this weakness, be it from factory defect or just poor design.
Either way, I'm sure the retailer, or Corsair themselves can sort you out. It's usually just a matter of having you send the faulty in for assessment then they send you out a new one.
Please keep us updated.