Issue with woocommerce_refund_line_items

Hi guys,
I am running TaxJar through jetpack and when we try to refund an item we’re getting the following error generated by the woocommerce-services-new-order-taxjar-2.4.1.js file inside of Jetpack.

VM31754:1 Uncaught SyntaxError: Expected ',' or '}' after property value in JSON at position 165 (line 1 column 166)
at JSON.parse ()
at HTMLDocument. (woocommerce-services-new-order-taxjar-2.4.1.js:1:1153)

The string we’re trying to parse looks like

{"action":"woocommerce_refund_line_items","order_id":"38812","refund_amount":"","refunded_amount":"5","refund_reason":"","line_item_qtys":"{}","line_item_totals":"{"99046":0,"99047":0}","line_item_tax_totals":"{"99046":{"42":0},"99047":{"42":0}}", ...}

It looks like there’s an issue with the way the line items are being generated here in /woocommerce/assets/js/admin/meta-boxes-order.js

                var data = {
                    action                : 'woocommerce_refund_line_items',
                    order_id              : woocommerce_admin_meta_boxes.post_id,
                    refund_amount         : refund_amount,
                    refunded_amount       : refunded_amount,
                    refund_reason         : refund_reason,
                    line_item_qtys        : JSON.stringify( line_item_qtys, null, '' ),
                    line_item_totals      : JSON.stringify( line_item_totals, null, '' ),
                    line_item_tax_totals  : JSON.stringify( line_item_tax_totals, null, '' ),
                    api_refund            : $( this ).is( '.do-api-refund' ),
                    restock_refunded_items: $( '#restock_refunded_items:checked' ).length ? 'true': 'false',
                    security              : woocommerce_admin_meta_boxes.order_item_nonce
                };

Any help would be much appreciated!