How can I set the default location when adding an item to a Physical Inventory?

I can enter a Physical Inventory by going to the following menu: Warehouse>Inventory Control>Physical Inventory and then clicking new, and then clicking Add item. In the new line that appears, the first field is the Location and it is filled with something like "internal / Stock". Sometimes this is ok but sometimes were are performing an inventory at a different location and this means we have to change the location every time we Add and item. It would save us a step if we didn't have to, if this field was set to whatever location is currently being inventoried.

The "Fill Inventory" button has no effect in this regard.