I tried taking a picture, but couldn't quite get one.
Having said that, I never made much effort, because I'm sick of getting Apple products with issues (my new AirPods Pro for example, the case is losing charge when not in use & the buds are constantly showing as charging, even though they are at 100%) so I just boxed it up for return!
However, I got it back out again (I really couldn't be bothered with the Apple exchange game) and gently massaged what looked like chips, and they faded away.
It must have been simply that the outer display wasn't completely stuck down?
Try it with yours, if you have the same issue. Use a microfibre cloth (I used the black one, that used to be supplied with all Macs) and I massaged the areas away.
Here's irony for you: After I completed that last sentence, I closed the lid and heard the feint noise. Closed it several times more, and never heard a thing. I truly hope it's just because it's new, and it just needs wearing in/loosening up?
I know you've already answered this, but I have to ask again: Would you just keep it?
No other issues: Good screen with zero dead pixels (which is a miracle!) good speakers, good everything, really.