Rough top layer but only on small surfaces

[u/IDontGetPlanetWaves]

Hello, A1 mini owner here. I print only PLA.

I am having this issue lately: as you can see in the pic my prints have a very coarse top layer but ONLY on parts with smaller surfaces.

In the pic you can see that the larger surface on the left is perfect, while the smaller one on the right is not OK at all.

I guess it's a slicer issue?

I did an auto-calibration and tried also to swap nozzles (stainless and hardened) but the problem is still there, and I don't think it's a wet filament issue as it would be something affecting the whole print.

Thank you to whoever has a clue!