If I can go back a few posts, icabodcrane mentions the half hour checks. Yes I agree but that was only the McCanns. You are forgetting the others who are either checking or passing the apartment regularly. Any noise would have been heard by them in the stillness of the night. The McCanns would have taken this all into account before making their decision to leave them in the bedroom.
It never crossed their mind that their apartment was being watched and that an abduction was being planned.
I have no doubt that this was not an opportunist crime, this abduction was carefully planned to the minute and Jane Tanner nearly thwarted it.
That's a fair point John
'In between' the half hourly checks the McCanns made, there may , indeed have been 'audio' checks made by others who were to'ing and fro'ing
Here's a question though ... why was it that the McCann children were checked frequently by others in the tapas group ( according to statements ) whilst the McCanns, on their
own checks, never listened in on any of the other children in reciprocation ?