"It is not yet possible to determine the date of the dialogue recorded in the CVR (Cockpit Voice Recorder), given that this equipment does not record this information," he continued, adding that an investigation would determine what may have happened.
The couple also worked in an experimental form of sound films, with dialogue recorded on synchronized phonograph records.
The game has more than 50 actors, delivering thousands of lines of dialogue, with foreign dialogue recorded in Pashto, Gulf Arabic and Chechen.
In certain other countries, notably Italy, most dialogue recorded during production is meant merely to serve as a guide track, and nearly all sound is added during postproduction.
"Counterman," written in dialogue, records the back-and-forth between a deli worker and a customer whose sandwich request takes an ornate turn.
"However, and crucially, there is this huge amount of story in there, with every line of dialogue recorded, and genuine moral choices to be made, with long-reaching consequences on how you experience the world," he told the BBC.
The idea for the piece came about by Waters experimenting with the rhythm of a dripping tap, which combined sound effects and dialogue recorded by Mason in his kitchen with musical pieces recorded at Abbey Road.
