Strange noise from rear

[i23b]

Hi
I have 2020 mk3 Leon.i heard some noise from rear side.Its sounds like rattle.This sounds takes about 10-15 seconds.Usually i heard this sound after braking.I'm not sure but if i don't press the brakes, this sound doesn't come. It doesnt always happen.This sound doesn't come from rear seat mount or trunk.

 

[nd-photo.nl]

Loose heat shield? Or splash guard behind the brake discs?

 

[i23b]

Loose heat shield? Or splash guard behind the brake discs?

maybe,i dont know.i will check this parts.