Apple LED 27-inch Cinema Display Buzzing Sound

Hi, I recently pick up an extra Apple LED Cinema Display on Craigslist and noticed that there was a constant buzzing noise from the fan in the back. The owner didn't mention anything about the buzzing sound when he sold it (yay) and I didnt noticed it when I turned it one. It only begins once the computer is warm. A few people have walked by my desk and asked if there was a bug flying around or what was that strange buzzing noise. Its a noticeable noise that can be heard from 5-10 feet away. Its coming from the fan area on the back of the monitor and is consistent, with the occasional quick break. I tried to do some research online and see if its possible to replace the fan or what might be causing it. Some places recommended SMC Fan control (https://www.macupdate.com/app/mac/23049/smcfancontrol) but I didn't want to play with that until I posted something here first.

Apple LED Cinema Display

27-inch (2560 x 1440)

Intel Iris 1536 MB graphics

Would love to know if anyone else has seen this happen and what can be done to resolve it. Thanks!