Related Clues:

• Low-volume sounds
• Wind sounds
• Breeze noises
• Library volumes?
• Soft sounds
• Speaks soft and low
• Speaks very softly
• Sh! Wipers must keep their voices down
• Breaths words rather than voices them
• Soprano's initial exercises going through hums and unvoiced words
• Secret messages misconstrued by Chinese?
• Talks very quietly
• 'Two drinks coming up' -- second causes grumbles
• Speaks softly
• Soft talk