From Longman Dictionary of Contemporary Englishdie down phrasal verbQUIETSTOP HAPPENINGif something dies down, it becomes less strong, active, or violent Don’t worry, the gossip will soon die down. when the excitement had died down → die→ See Verb table
Examples from the Corpus
die down• The barbecue won't be ready until the flames have died down and the charcoal is glowing.• The music was dying down. The show was over.• Forrester waited for the laughter to die down, then carried on with his speech.• Jessie's wails died down to a whimper and then stopped altogether. 