@David-Healey
Thanks for giving it a try – yeah I've been trying something out in Scriptnode – but succes here yet. Maybe I aimed too high for my current skills hahah :-)

Hey Christoph !
Thanks for your quick reply !
I just added a velocity modulator and it worked perfectly !
The pan is just how the note is in the space like left, right. I tried to load a StereoFX but yeah it crashed, so I'll learn how to compile the source when I'll have some time.