27" inch thunderbolt display buzzing brightness setting

My 2012 27" Thunderbolt Display recently (past 2 weeks) started a loud buzzing (electrical-sound) when the brightness of the display is modified brighter or darker.

At 100% brightness, the sound is very audible. Very annoying. Less audible but still buzzing even at the lowest brightness setting.

My display has sat on my desk and not moved more than one time in the last 18 months that I have owned it.

I run external audio and when the audio is completely unplugged and muted, the buzzing is still relative to the brightness-settings.

It's noticeably located on the bottom-left side of the display (when facing it). Moving the display tilt using the back stand-hinge doesn't change the buzzing.

Is anyone else experiencing this?

Does anyone know if Apple is recalling these or fixing them based on a recall due to this sound?

Some forum discussions say that this could be the transformer?

Any suggestions would be helpful.