diff --git a/core/gallery/class-mpp-gallery.php b/core/gallery/class-mpp-gallery.php
index 3a03c36..f26684d 100644
--- a/core/gallery/class-mpp-gallery.php
+++ b/core/gallery/class-mpp-gallery.php
@@ -239,7 +239,7 @@ private function map_object( $_gallery ){
 		foreach ( get_object_vars( $_gallery ) as $key => $value ) {
 			
 			if ( isset( $field_map[ $key ] ) )
-				$this->$field_map[ $key ] = $value;
+				$this->{$field_map[ $key ]} = $value;
 			
 		}
 		//there is no harm in doing this
diff --git a/core/media/class-mpp-media.php b/core/media/class-mpp-media.php
index 8713be3..bb85d4a 100644
--- a/core/media/class-mpp-media.php
+++ b/core/media/class-mpp-media.php
@@ -285,7 +285,7 @@ public function map_object( $media ){
 		foreach ( get_object_vars( $media ) as $key => $value ) {
 			
 			if ( isset( $field_map[ $key ] ) )
-				$this->$field_map[ $key ] = $value;
+				$this->{$field_map[ $key ]} = $value;
 			
 		}