Ok that confirms what I was thinking about tolerances (tried changing them and not that much of a difference in the code).Adding something to this about accuracy or precision numbers in Fusion (or any CAM for that matter): those only apply when it's doing conversion of non-arc curves (splines, ellipses) or surfaces into line moves. If your output is G02/G03 moves, accuracy doesn't weigh into the problem.
Arc moves are strictly up to the control to execute them right or wrong. If anything, you should be checking the Yasnac control if it has its own tolerance / accuracy setting for how fine it breaks up circular moves.
As already posted: speed might be a factor. The extremely small amount of clearance between rough and finish cuts probably plays into it. If you're jamming a cutter down there and doing full-depth cuts, that also plays into it. I'd personally do a helical cut around each of those posts and not treat them like pockets.
The artifacts left on the chamfers look like the cutter needs a rough and finish lap around the part. It's probably deflecting at the end and not completing the circle.
I will try to reduce my speeds as triumph also advised me to do.
Your idea of doing helical cut around each boss also seems better than doing a pocket.
Thanks a lot for all theses advices !