X-Carve Laser lines bad

Hallo togehter,
I have a problem with my laser, if the laser changes the direction I will get bad lines.
If I work with pictures so I can fix the problem by overrun mode.
But if I use text or lines so I see the problems again.
Have anyone an idea what is the problem. See the pictures.
The speed isn´t very high (1200).



Thank you very much.