Related Clues:

• Dull sound
• Guitar sound
• Engine sound
• Drone
• Play a guitar idly
• Play idly, as guitars
• Monotonous sound
• Rhythmic sound
• Single thread
• Finger-tap on a tabletop
• Harp sound
• Pluck guitar strings idly
• Play banjo idly
• Pluck idly
• Rhythmic humming sound