All the filament i tested today was previously dried in a food dryer and stored in vacuüm bags.
I think i found the issue on one of them in the extruder idler gear axle which had came out of the handle at one end. I guess the jerks on the extruder make it work it’s way out through vibrations, causing the extruder to lose it’s grip on the filament causing under extrusion.
I printed a small plate and glued it on the handle to prevent the axle from working it’s way out again.
Benchy are printed fine again in different filaments, now started something bigger.