Groan sound when closing screen.

[vbman213]

I have started to notice that every time my screen is open for a long period of time, it makes a weird groaning noise when I close it. The sound is coming from the left-hand side (the logic board side).

however, I never hear this noise when I open the screen. And if the screen is moved periodically, the noise is not heard. It is only when the screen is open and stationary for a period of time.

What could this be?

 

[ideal.dreams]

I don't know if there's any similarity, but a few weeks ago I noticed a sound coming from my MBP when I shut it, too. It took me a while to figure out what was making the noise but it turns out the black piece of plastic that covers the hinges was moved to the left and the display was crunching it when it closed. I slid it back to center and it stopped making noises.