Use the node ‘DoOnce’ and plug it in before your PlaySound.
Please note that the ‘ResetMyThing’ Event is optional, and you do not need to use it. However this would allow you to reset this circuit and have your Sound Play again.
For example: Player opens door, the Sound plays, but cannot be played again.
When the Player closes the door the Reset Event is called, and for the next door opening the sound would play again!