<!DOCTYPE html>
<html lang="pl">
<head>
<meta charset="UTF-8"/>
<title> title </title>
</head>
<body onload="setTimeout(playSound, 1000);">
<audio id="audio" src="test.mp3" loop ></audio>
<script>
function playSound() {
var sound = document.getElementById("audio");
sound.play();
}
</script>
</body>
</html>