Shopify eBay app - eBay modifying weights when purchases are made


I am using the eBay app with Shopify. I am seeing the weights for my listings change when people order items. It usually increases the weights to 0.9877. Most of my products are under 1.0 ounces. 


I contacted the Shopify eBay app support team, who initially told me my listings were showing to them as being existing listings on eBay, but that was not correct -- they were all added via the eBay app in Shopify. 


Next, I was told to edit the listings in Shopify and in the eBay app (within Shopify admin) to the same weight values, and once they were the same, the sync would be maintained going forward. 


This did not work. Although initially, after an eBay order both the Shopify listing as well as the eBay listing details were modified (to the 0.9877 oz. weight), after I manually edited/synced the weights, an eBay order no longer changed the Shopify listings. Only the eBay listing weights. 


When I view the listings within eBay, I see the weights listed as "1 lb. or less" in the drop-down, and "1 oz." in the text entry field. In the eBay app on Shopify, the most recent listing shows the same, 1.00 oz. 


The Shopify eBay app product details screen has a note to "Leave empty to use the Shopify values. Weight and Barcode changes will be updated back to Shopify", but when I delete the existing weights, it still reads a grayed-out "1.00" in the oz. text field. 


As you can imagine, this is making my shipping costs very inaccurate when people try to order multiple items. 


Has anyone experienced this before, and have any solutions/suggestions?

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