Ti scrivo un esempio di codice php.
Codice PHP:
<?php
$link_arr = array("link_imm1", "link_imm2", "link_imm3", "link_imm4");
$i = rand()%4+1;
$link = $link_arr[i];
?>
<html>
.......
<body>
...
<embed src="<?php print $link ?>" loop=true autostart=true hidden=true mastersound>
<bgsound src="<?php print $link ?>" loop="infinite">
...
</body>
</html>