Possible Clues:

• ''I ___ Symphony'' (Supremes hit)
• ''Do I ___ second?''
• With 36-Down, what you can't do regarding this puzzle's circled letters
• '... -- pin drop'
• "Do I __ Waltz?": Rodgers/Sondheim musical
• 'You could -- pin drop'
• "I __ Symphony": Supremes hit
• -- pin drop
• '... you could -- pin drop'
• Supremes song 'I ___ Symphony'