Delta bad print quality

[PuddingBaer91]

hi there

i have an anycubic predator but i can't get good quality prints. First i have to say i don't use a duet wifi with this printer at the moment but i have a core xy running the awesome duet. I instead posting here in the duet forum because i think here a delta experts.

I tested with Marlin and also with klipper und i get the same results. I have done the delta calibration on both systems.

I am not asking for help with firmware settings because many other people using the exact same config i assume it is not a sotware problem. I also checked my printer and it is really smooth and rod lengths are also very close. Tower distances also very close:

that is what i get from klipper calibration:
Recv: // stepper_a: position_endstop: 453.906809 angle: 209.935163 arm: 440.000000
Recv: // stepper_b: position_endstop: 454.878925 angle: 329.704862 arm: 440.000000
Recv: // stepper_c: position_endstop: 454.402357 angle: 90.000000 arm: 440.000000
Recv: // delta_radius: 226.537203

with marlin i get a stdev about 0.32

I hope you can help me to find the problem. I think it is a machanical issue. What do you think? (z direction = left/right)

thank you very much!