Virtuemart order by product name orders by category name.

[jucedupp]

Hi guys.

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Virtuemart Version: 2.0.24

I have added extra sort by fields via the back end.

When I click on Sort by: Product name +/- on the manufacturer category page it sorts not according to product name, but according to category name. 

Default Sort URL: http://mywebsite.com/index.php?option=com_virtuemart&view=category&Itemid=&filter_product=&keyword=&limit=150
Descending sort: http://mywebsite.com/index.php?option=com_virtuemart&view=category&Itemid=&filter_product=&keyword=&limit=150&order=DESC

This definitely sorts according to category name and not product name.  Any ideas as to what may be causing this?