diff --git a/Plugins/FileSource/FileSource.m b/Plugins/FileSource/FileSource.m
index e95733b7c..6d6e6a7cd 100644
--- a/Plugins/FileSource/FileSource.m
+++ b/Plugins/FileSource/FileSource.m
@@ -90,7 +90,13 @@
         
         return (position >= 0) && (position < size);
     }
-    
+	
+	if ( _fd == NULL ) {
+		offset = 0;
+		size = 0;
+		return NO;
+	}
+	
 	return (fseek(_fd, position, whence) == 0);
 }