H60 pump Buzzing/Grind sound

Hi, I'm on my 2nd H60 but I'm still getting that troubling sound from the pump.

I've tried the aforementioned solution of putting my PC on its side for 24hrs which only mitigated the sound the whilst it was positioned like that.

I also read on the Corsair forums that another cause for the problem was PSUs that provided higher than 12.2V on the +12V rail which is the not the case for mine.

I'd like to know whether I'm better off requesting an RMA with the e-retailer I bought the cooler from or Corsair directly since you're more likely to have one of the newer versions of the unit which doesn't have this problem?

Thanks.