STRIP MALLS, MOVIE theaters, schools, grocery stores — the images in Speaking Is Difficult, the new film by Field of Vision co-creator AJ Schnack, are ordinary but serene. Wherever we live, these are the places where we routinely expose ourselves to the wider world. The film punctures this calm familiarity with grainy audio documenting past traumas. The details we can ascertain from these 911 recordings are sparse — a white male shooter, an unknown number wounded — but we all know how to fill in the blanks. In one sense, we’ve seen this movie before.