So after a lot of swearing and googling every single parameter I found something interesting about the PWM Scale (Y Axis Overdriving and Blowing Driver)
One of those guys got in touch with Watterott and was told that the USB Cable (more the 5 Volts) which is connected to a raspberry Pi in my case, can cause some wierd stuff on the Y driver (high current... just read it yourself). So I thought what can I lose ordered a new MKS Gen1.4 and connected everything except the Raspberry.
And now everything works just fine and this damn y-motor is quiet. :D
One of those guys got in touch with Watterott and was told that the USB Cable (more the 5 Volts) which is connected to a raspberry Pi in my case, can cause some wierd stuff on the Y driver (high current... just read it yourself). So I thought what can I lose ordered a new MKS Gen1.4 and connected everything except the Raspberry.
And now everything works just fine and this damn y-motor is quiet. :D