Martin, your screenshot shows exactly the problem, it shows A4 with a frequency of 880Hz A4 has a frequency of 440 Hz and cubase cannot change that scientific fact, if a string vibrates at 440 Hz the tone you hear is A4. Cubase using C0 to start puts their A4 at what the rest of society know as A5, so by typing in the note name you are placed at the wrong frequency, if you are working all within Cubase their keyboard matches their frequency chart. their pianoroll A4 matches their frequency plugin A4, but in the real world their A4 is at the frequency of the real worlds A5 880 Hz, or thats what my Uni tutor taught us, I’m sure he has his facts right.