Quantities shown with mini-cart

Hi, I am trying to customize my mini-cart by adding the 'proceed to checkout' button. I'm simply using the same button that's used in the regular cart with a copy-paste of this line:

<?php echo $this->cart->displayButton(JText::_('PROCEED_TO_CHECKOUT'),'checkout',$this->params,hikashop::completeLink('checkout'.$url_itemid),''); ?>

Which works for the most part except that there is now a Quantities input box (see screenshot). I've already checked my Cart module and 'show quantities in cart' is set to NO. Appreciate any input/help.

Please add $this->params->set('show_quantity_field', 0); just before the code of your button.