ABS only gave more problems. In addition to the "skipped layer" problem, after a few layers the nozzle started scraping the the print. At some point the infill and wall of the print came loose and i ended up aborting the print. (The infill also looked awful btw....).

Tried some more tivial settings.

-Lower retraction to 0.5 mm @ 40 mm/s (didnt give problems before)
-temp to 235 (ABS)
-checked calibration once again
-lowered speed to 20 mm/s
-travel speed to 100 mm/s

next things:
- check Z stepper voltage (Did slightly reduce some stepper voltages, not sure if i included Z or only lowered X and Y)
- check jerk settings
- General firmware settings check

As always suggestions are welcome.