Related Clues:

• Dolphin's navigation aide
• Do likewise
• Repeat verbatim
• Returning waves, of sorts
• Radar-screen spot
• Rever-berate
• Resonate
• Repeat performance
• You've heard this before
• Radar screen sound
• Sound reflection
• Sound that's coming back?
• Utter an identical sentiment
• Yodeler's feedback, perhaps
• Brief interruption