Sadly yes - you purchased a poorly designed / manufactured Rev A notebook from a company that has lost sight of quality assurance.
I own a reasonable amount of Apple stock and love the paper gains. I run my business on Macs and am not impressed with what they are allowing to happen to the quality of their notebook line.
If it bothers you I would call Apple and return it for repair. BTW - are you referencing the screen buzz, cpu higher pitch whine, or buzz from the power brick?