I have a new scenario, i changed the nozle, calibrate again and print a perfect calibration cube from the sd card the one, then i make a stress test, 5 objects with support material. The print runns 3 hours very exact and really good, but the suddenly the filement get out too slow for the fast move of the printer (normal settings like them from ethan) and additional the clicking noise. Hotend was fine by 210 C and i not really now why it happen such adhoc during the print.
The old nozle was nearly burned out, therefore i changed it, the new nozle 0.3 runns fine directly, no clicking nothing, fast extrusion of filament, but now after 3 hours printing the nozle is not able to extrude as fast as before....