Ok but you can easily have both looping and a pause ... a user might need take a break from all the mosquito noise but not want to close the app If you get more user feedback asking for a pause functionality you might want to think about it again

Edit: oh you've changed your post a little.. yep when you exit the app it stops playing all sounds, it would be terrible if the mosquito sound continued to play in a loop long after the app had closed lol! I think what was suggested was a way to stop or pause the sound playing during when the app is open. It's something to think about