Okay, I tried several thing, don't know if they all made sense to test:
1. I played files over MusicBee on a Virtual PC --> still chirping
2. I played files over MusicBee on my Notebook (same Windows Version as my PC ) --> still chirping
3. I used a external Sound-Card (USB connected to my Notebook) --> still chirping
On all of that I changed settings like we discussed earlier
I tried the windows media player each time --> no chirping
I noticed that the whole song sounded less processed on the other players. On MusicBee there were less random noise / hissing.
What is different here? There must Bee a way