Possible Clues:

• Sounds as if this is able to cause amusement in church
• The sort of church music that's able to make one go 12 across?
• The sound of this sacred music is able to amuse one
• Can such church music make one laugh, by the sound of it?
• One of the 24 across from 2 down that may be able to make one giggle with its sound
• Such church music is able to get you giggling, by the sound of it
• Cancel it in error and there'll be a song made!
• Short hymn
• Religious music with archaically grotesque line in church
• Humbug used by one semi-intelligent is heard in church