Clones can't play the same sound at the same time. In the Clones sprite: - When the green flag is clicked, one clone is created, and after a 1 second delay, another clone is created. - Under the "When this clone is created"-block, the clone tries to "play sound [A]". I copied the library sound "A Elec Piano" five times in the same sound clip. In the illustration, you see how it should sound, and you should see and hear that it doesn't work for two clones to play the same sound at the same time. All code by me (@kriblo).