Mild Buzzing Under Keyboard

[Optimus Primes]

I was cleaning my keyboard today and I heard a mild buzz from under the keyboard. Its definitely not the fan because I turned the rpms up and it didnt change. Its sort of an electrical sound. Its not audible when sitting up but you can hear it when you lean in.

I read articles about apple asking you to contact apple care if you hear buzzing noises. Is my noise what they are talking about?

 

[GGJstudios]

Apple Portables: Hard drives and noise

 

[Optimus Primes]

This isnt the hard drive either. I have a 15 in MBP and this is way off where HDD is located. I can hear it under the keys t and 6. Slight mild electrical buzzing.