Warning: A non-numeric value encountered

I am happy that I found your plugin, but unfortunately I have one issue that keeps popping up. When the “Name your own Price” field is left blank, and you try to add to cart, the following error shows up:
Warning: A non-numeric value encountered in /wp-content/plugins/woocommerce/includes/class-wc-cart-totals.php on line 234
It seems that the plugin tries to pass a non numerical value instead of just a zero, when there is no value.
It would be great if this error could be quashed. ??
Thanks!

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