When the diaphragm goes back and the random 'Whistle' starts. Where is this actually venting from?

Is it the front or rear crank seals or both?
When this start and if it is the crank seals what damage comes along with it to the seal.

Is there any place else on the valve cover that has a rubber diaphragm that goes bad?
More curious than anything, considering that BMW changed the CCV from the N52 where it was a separate unit

If it is not the crank seals on the N52N, then where it 'Whistling' from and as the whistle is pretty omni-directional?