Possible Clues:

• "Shut up already!"
• "Stop complaining!" ... and a hint to the words hidden in the starred clues' answers
• Shout to someone with a blindingly bald head?
• ''Zip your lip!''
• "Hush!" to a hatter?
• ''Enough already!''
• ''Enough!''
• "Stop complaining!" (and what you might do to the start of 17-, 33- or 41-Across)
• "Shut up!"
• "Hush!" (and hint to how 4-, 9- and 21-Down are formed)