diff --git a/src/avfoundation.cs b/src/avfoundation.cs
index 6ffa42cb135c..9eba5bf3a075 100644
--- a/src/avfoundation.cs
+++ b/src/avfoundation.cs
@@ -2918,7 +2918,7 @@ interface AVAsset : NSCopying {
 		[Export ("metadataForFormat:")]
 		AVMetadataItem [] GetMetadataForFormat (NSString format);
 
-		[Wrap ("GetMetadataForFormat (new NSString (format.GetConstant ()))")]
+		[Wrap ("GetMetadataForFormat (format.GetConstant ())")]
 		AVMetadataItem [] GetMetadataForFormat (AVMetadataFormat format);
 
 		[Export ("hasProtectedContent")]