I have Magento ver. 1.9.3.0. I have 2 stores, each for different country.
Everyday my shop synchronizes prices with ERP system by cron. If price for one product was changed in ERP, then cron sets new price for that product.

I have noticed that every time after synchronization, Default Value checkbox is unchecked for changed product in General section. It is very annoying to check all checkboxes, even after I have set all them day before. I have no idea why it happens.

There is main cron function, that updates product:

public function prepare($  store, $  ids, $  productId) {     $  updateProduct = false;     $  product = Mage::getModel('catalog/product');     $  minPrice = null;      if ($  store) {         $  product->setStoreFilter($  store);         $  product->setStoreId($  store->getId());     }     $  product->load($  productId);      $  collection = $  this->getSimpleProductsByIds($  ids, $  store);      foreach ($  collection as $  simple) {         $  price = $  simple->getPrice();         if ($  price > 0 && (is_null($  minPrice) || $  price < $  minPrice)) {             $  minPrice = $  price;         }     }      if ($  product->getPrice() != $  minPrice && !is_null($  minPrice)) {         $  updateProduct = true;         $  product->setPrice($  minPrice);     }       $  configurableArray = $  product->getTypeInstance()->getConfigurableAttributesAsArray();     foreach ($  collection as $  simple) {         $  price = $  simple->getPrice();         $  valueIndex = $  simple->getData('size_simple');          if ($  configurableArray && isset($  configurableArray[0]) && isset($  configurableArray[0]['values']) && $  configurableArray[0]['attribute_code'] == 'size_simple') {             foreach ($  configurableArray[0]['values'] as $  key => $  value) {                 if ($  value['value_index'] == $  valueIndex) {                     $  diff = (float) ($  price - $  product->getPrice());                     if ($  diff != 0 || $  diff != $  value['pricing_value']) {                         $  updateProduct = true;                         $  configurableArray[0]['values'][$  key]['pricing_value'] = $  diff;                         $  configurableArray[0]['values'][$  key]['use_default_value'] = 0;                         $  configurableArray[0]['values'][$  key]['is_percent'] = 0;                     }                 }             }         }     }     if ($  updateProduct) {         $  product->setCanSaveConfigurableAttributes(true);         $  product->setConfigurableAttributesData($  configurableArray);         $  product->setData('update_price', 0);         $  product->setData('bold_catalog_update', 1);         try {             $  product->save();  // there is something wrong         } catch (Exception $  e) {             return false;         }     } else if ($  product->getData('update_price') == 1) {         try {             $  product->setData('update_price', 0);             $  product->getResource()->saveAttribute($  product, 'update_price');         } catch (Exception $  e) {             return false;         }     }     return true; } 

$ configurableArray looks like that:

array(1) {   [0]=>   array(9) {     ["id"]=>     string(4) "2353"     ["label"]=>     string(11) "Size Simple"     ["use_default"]=>     string(1) "0"     ["position"]=>     string(1) "0"     ["values"]=>     array(2) {       [0]=>       array(9) {         ["product_super_attribute_id"]=>         string(4) "2353"         ["value_index"]=>         string(1) "3"         ["label"]=>         string(5) "S/M/L"         ["default_label"]=>         string(5) "S/M/L"         ["store_label"]=>         string(5) "S/M/L"         ["is_percent"]=>         int(0)         ["pricing_value"]=>         NULL         ["use_default_value"]=>         bool(true)         ["order"]=>         int(6)       }       [1]=>       array(9) {         ["product_super_attribute_id"]=>         string(4) "2353"         ["value_index"]=>         string(1) "6"         ["label"]=>         string(6) "XL/XXL"         ["default_label"]=>         string(6) "XL/XXL"         ["store_label"]=>         string(6) "XL/XXL"         ["is_percent"]=>         int(0)         ["pricing_value"]=>         NULL         ["use_default_value"]=>         bool(true)         ["order"]=>         int(11)       }     }     ["attribute_id"]=>     string(3) "133"     ["attribute_code"]=>     string(11) "size_simple"     ["frontend_label"]=>     string(11) "Size Simple"     ["store_label"]=>     string(7) "Rozmiar"   } } 

There is a key: use_default_value, but I have no idea to what it points.