Magic - or how????

moin moin, or better happy oster!!!!
so, this is not an ostermarch!!!!
I make a pre-osterical flight with the whole family and hear a resonating sound from behind li.! when I take the foot off the accelerator, this noise is suddenly gone. so I combine - is related to the gas-giving. so far so good. we are back, standing in front of the house door, I turn off the car and that noise reappears, in the stand well noticed, with the engine switched off!!! I clearly get off, go around the car and realize the noise comes from the corner of the footroom behind the passenger seat.
you know this noise, when you rub with a finger on the edge of a wine glass, the glass is vibrated and a floating sound is generated! - that's exactly how it sounds, just stopped as wehrs made by 8 fingers (if you understand...) so a strong tone fluctuating in height, but not high frequency!!! after 2-3 min. The haunted is over and the sound abruptly breaks off as while the energy ends.
I know that whole sounds pretty sticky, but I can assure you that I am serious and I am urgently looking for an answer!
I already see the audi filiale, what they want to sell me...!!!
It's funny, too, it only seems to occur when you've been driving longer than you've had to charge up a bit, or something like that.
I knelt myself short next to the car and saw that there is also a lot of underbody clothing in the vicinity of the rear right mature.
Does anyone have any idea what that can be? and is that fermented? what is sitting in the corner, which has a stromanschloss?
Well, I'm curious what my wife will tell me when she hears this noise...! "I said right away, if we had kept the old car - bla bla bla!!!"
I wish all friends of the sonoric feeling, a quiet and beautiful Easter festival!
- or as my friend used to say: "space instead of spoiler!!!" - no!
ciao jörg
- who soon has "EURO2" in the letter - ho ho ho!!!