Answer: droners

AnswerCrossword Clue
DRONERSThey go on and on
DRONERSTiresome speakers
DRONERSMonotonous speakers.
DRONERSBeetles in flight.
DRONERSDull, monotonous speakers
DRONERSBumblebees
DRONERSSteady hum producers
DRONERSDull lecturers
dronersto speak in a dull, monotonous tone
dronersdeep humming sound
dronersDRONER, one that drones (to make a monotonous humming sound)
dronersto make a deep humming sound