Who Is The Whistling Person?

I had just done an S3 Service on the Thrandter Rampe with the Talent2. When I arrived in Tharandt, I suddenly heard someone whistling a two seconds Melody.

Two Question
Have you ever noticed that yourself and who do you think has immortalized himself in the Game?

Before you ask, it must have come from the Game, it was the only thing in my Room that made a Noise.

 

Since the rush hour passenger update , I’ve noticed whistling as well . It’s a cool feature IMO

 

Plot twist:
It’s your demon from the Wardrobe