Related Clues:
- Refrigerator noise
- Air-conditioning sound
- Droning sound of instant message when holding on
- May sounds with a closed mouth
- Sing with one's mouth closed
- Tedious talking style
- Not quite sing
- Second, not first number that is unmelodic
- Lacking expressiveness
- Drum starter?
- Dull delivery
- Vocalize on a kazoo
- Sing with a closed mouth
- Smell and sound of bees
- Smooth machinery sound