Continuity mistake: When the helicopter lands we see it is sitting over the white circle of the landing zone on the back of the ship. Later, right after the F18 is shot down, we see an aerial view of the ship with a small part of the back cut off, but part of the landing zone circle is visible and there is no helicopter. (00:13:30 - 00:36:00)
Continuity mistake: Before Admiral Bates first speaks to Strannix, there is a dark-haired marine in a green uniform on his left. When Bates raises his hand to signal activating the audio to speak, Captain Garza (black uniform and silver hair) is suddenly on his left. Then it changes to another camera angle and the marine is back next to Bates. (00:36:40)
Answer: Also, the more times the scene is practiced or additional takes, the less funny it is to the actors. So, it would be easy by the time of filming for Strannix to not laugh. Just like if you have seen a classic comedy TV show, the audience is always laughing because it's generally their first time seeing the scene when filmed. But you as a viewer, seeing the show a hundred times over the years, do not laugh because you have seen it so many times. That, to YOU, it's not funny anymore. Same rules apply here for the actors while filming.