Related Clues:

• Clue for a car mechanic
• It's not in the library often
• Annoying sound
• Night sound
• Sleep preventer
• Nocturnal sound
• Midnight rumble
• Sleep trouble
• Intake interruption while asleep?
• Nocturnal annoyance, perhaps
• Really bad music, to the listener
• Sound caused by the soft palate's vibration
• Sound made while sacked out
• Breathing irregularity
• Librarian's bane