Specific print failing always at the same point

[paoletto 3]

Hi, I have a specific print, actually a setup i have already successfully printed before to which i changed the model to a modified version, that keep failing (4th time) always around the same time.
The problem seems to be retraction settings (i think) and the filament end up ground like in the picture https://imgur.com/a/0ikNras
I tried to modify the Travel settings, reducing retraction count to 5, increasing minimum distance to 10mm and reducing retraction distance to 4.5mm.

I also verified the filament puller to be clean inside, and tried to increase spring tension a bit.

I believe it might have had some effect since all previous failures ended up with one single ground point along the filament, after the change in the last print i have 6 ground points.
I also see and hear that in the beginning of the print retraction works fine, with the characteristic standard sound.
Then at some point grinding begins

Any quick tip?

Edited May 28, 2022 by paoletto