Precuing impossible

I use an Imac 2011 and djay pro 1.4.3., osx sierra. Spent hours trying to precue…no matter what i try, i just get a constant peep sound out of my headphones. Every possible configuration fails - precuing is just peeping loud.
However, in djay 4 everything works just fine. How is this possible?

Hey there,

which device are you using in order to Pre Cue?
Please give us more information about your setup.

Can you send us a screenshot of your audio device settings while using one device?

Hey Lukas,

i use an external usb card, the Griffin imic. But it is the same with bluetooth and usb headphones (August EP650B). Also the traktor splitter cable doesn’t work.

As said, all of these devices work just fine in djay 4 but not in djay pro.
Tried also different djay pro versions.

It was exactly the same on a imac 2007, osx el capitan.