Answer:
In the middle of night, I surround the gong. In the middle of sight, I end the song
What is seen in the middle of march and april?
What instrument can you hear but never see?
What can get you there in eco style, pushed by your legs mile after mile?
What is found over your head but under your hat?
I repeat only the last word you say. The more I repeat, the softer I got. I cannot be seen but can be heard. What am I?