In Switzerland, sirens are regularly tested. But we are not immune to hiccups. In July 2023, some sounded by mistake in the middle of the night, in Lausanne, due to a technical failure. This year, at the same time, Vaudois and Valaisans woke up in panic, after hundreds of alarm sirens were triggered by mistake, during a “mute” test. Rebelote a month later, in Lausanne, because of an act of vandalism.