diff --git a/classes/Cart.php b/classes/Cart.php
index 27ac63854..663b43152 100644
--- a/classes/Cart.php
+++ b/classes/Cart.php
@@ -588,7 +588,7 @@ class CartCore extends ObjectModel
 					((int)$this->id_customer ? (int)$this->id_customer : null),
 					(int)$this->id,
 					((int)$address_id ? (int)$address_id : null),
-					null,
+					$null,
 					true,
 					true,
 					$cart_shop_context
diff --git a/classes/Product.php b/classes/Product.php
index 05c802f4c..ba426d5f8 100644
--- a/classes/Product.php
+++ b/classes/Product.php
@@ -487,10 +487,8 @@ class ProductCore extends ObjectModel
 				die(Tools::displayError());
 			self::$_taxCalculationMethod = Group::getPriceDisplayMethod((int)$customer->id_default_group);
 		}
-		else if (Validate::isLoadedObject(Context::getContext()->customer))
-			self::$_taxCalculationMethod = Group::getPriceDisplayMethod(Context::getContext()->customer->id_default_group);
 		else
-			self::$_taxCalculationMethod = Group::getDefaultPriceDisplayMethod();
+			self::$_taxCalculationMethod = Group::getPriceDisplayMethod(Group::getCurrent()->id);
 	}
 
 	public static function getTaxCalculationMethod($id_customer = null)