Possible Clues:

• Choruses
• Choruses of songs
• *Whistle blowers
• Repeated parts of songs
• Holds back parts of songs
• Rules broadcast by football official for songs
• 'Fa la la la la la la la la' and others
• Doesn't do to have recurrent themes
• Parts of compositions. suggested by 69-Across
• Burdens judge with buckets