Please note that all stories templates are muted by default with respect to the user's experience and privacy. Taking the below steps will lead to unmuting your story's template upon the user clicking on a story.
Log in to your Smart Stories dashboard.
Locate the group of stories you want to delete and click on the group to open it.
Click on "Edit Story" on the top right of your screen.
Click on "Templates" in the left menu. Look for the pen icon on the right side of the template name and click on it.
Tick the "Unmute on click" option and click on "save" at the bottom of the page for the change to be effective. Doing so will lead to automatically playing the sound of your stories once clicked.