Related Clues:

• Volume control?
• Quiet jail
• 'Stop talking!'
• Sounds like someone's giving order not to take statement in jail?
• "Too noisy!"
• Button it!
• "Cut the chatter!"
• "Shaddap!"
• Audible silencer
• Peremptory signal
• Quiet "Quiet!"
• "That's enough from you!"
• Warning that often precedes 17-, 30-, 49- and 65-Across
• Gag order?
• 'Not a word!'