While not quite what the OP asked about, it seems like NYPD car and ambulance sirens like to make themselves known during the quietest passages of a show. This is particularly irksome when the show is a period piece (e.g, Phantom, Les Miserables, etc.), so the siren is an anachronism.
==> this board is a nest of vipers <==
"Michael Riedel...The Perez Hilton of the New York Theatre scene"
- Craig Hepworth, What's On Stage