Hurray, now I got something who works flawlessly.

I've played with the dummy values (Dummy2=8745 and Dummy3=100), now I get the exact sines I want.

For 1200 for example (120*10=120.0Hz), I get 120Hz, for 500 (50*10=50.0Hz) I get 50Hz, for 357 (35.7*10=35.7Hz) I get 35.7Hz...

So now it works, I can go ahead in my project.

Thanks a lot Henrik for your help and your support.