Possible Clues:

• Being like
• Imitating a whistling sound
• Producing a copy on a high note
• Mimicking like monkey
• Acting like a parrot making a sharp sound
• It's high, by the sound of it, but not originally
• Burlesque activity
• Making copy of silver-coated brooch
• Copying small brooch in silver
• Copying a high thing, by the sound of it