diff --git a/sources/custom/MapInfo.cs b/sources/custom/MapInfo.cs
index 49af97fd0f..ab2cf2a71b 100644
--- a/sources/custom/MapInfo.cs
+++ b/sources/custom/MapInfo.cs
@@ -34,7 +34,7 @@ namespace Gst {
 				return data;
 			}
 			set {
-				Marshal.Copy (value, 0, _data, Data.Length);
+				Marshal.Copy (value, 0, _data, value.Length);
 			}
 		}