I’ve been having an issue with the top surface being wavy. It does it with my own designs and downloaded prints. So I’m pretty convinced its not my print settings. I just replaced my XY belt and there’s no change. Changing filaments, top surface pattern, infill density, number of top layers, layer height, all do not make a difference. I’m not sure where to go from here.
Such waves are usually a sign of slight overextrusion. Hence a new filament (auto-) calibration can help.
But there are other, less obvious reasons which can (usually locally) cause such overextrusion.
Warping for example leads to reduced upper layer heights and hence overextrusion.
In this case, ensure dry filament, a meticulously clean plate and a warm(ish) print chamber temp while considering brims/moise ears. However, warping can pull the build plate off the heat bed. In this case, lowering layer heights and/or print speeds can offer further improvements.
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Did it solve your problem?
Welcome to the forum 
Since you replied to me, I’ll tag @VaporiZe so your question will send a notification.
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