diff --git a/getid3/module.audio.dss.php b/getid3/module.audio.dss.php
index dd2a56b1..82a979a5 100644
--- a/getid3/module.audio.dss.php
+++ b/getid3/module.audio.dss.php
@@ -83,11 +83,11 @@ public function Analyze() {
 	 */
 	public function DSSdateStringToUnixDate($datestring) {
 		$y = (int) substr($datestring,  0, 2);
-		$m = substr($datestring,  2, 2);
-		$d = substr($datestring,  4, 2);
-		$h = substr($datestring,  6, 2);
-		$i = substr($datestring,  8, 2);
-		$s = substr($datestring, 10, 2);
+		$m = (int) substr($datestring,  2, 2);
+		$d = (int) substr($datestring,  4, 2);
+		$h = (int) substr($datestring,  6, 2);
+		$i = (int) substr($datestring,  8, 2);
+		$s = (int) substr($datestring, 10, 2);
 		$y += (($y < 95) ? 2000 : 1900);
 		return mktime($h, $i, $s, $m, $d, $y);
 	}