I came across a situation that reminded of a recent thread on cabin safety videos/demonstrations not being completed before takeoff. During taxi out on a U.S. domestic (carrier to remain nameless) flight recently the pilots announced "we are #1 for takeoff and flight attendants please secure the cabin for takeoff." The FAs immediately turned off the safety announcement which had already completed in English and was being replayed in Spanish. They then finished securing the cabin while the plane held short of the runway. Shortly after they sat down the plane turned onto the runway and took off. My question is this, if a domestic U.S. carrier plays a second language safety video are they required by the FAA to complete both videos or does playing only the English version satisfy FAA requirements.