How do I set the tax code to default in the Shipment Cost Document under the Tax tab? We're seeing different behavior depending on whether we're shipping from US to Canada or the other way around. It must be configurable but I can't find it. Please help as I've read many existing posts and can't find a resolution.
Here's what's happening:

2. B/L 122325 is in Company 1000, and is the reverse of the one above (US to Canada shipment). It has a Canadian Tax Jurisdiction with the Tax Code of I0, and it works fine. The Jurisdiction does not have to be deleted.

It seems that the issue with the Company 2000 shipments would be the Tax Code of I0 not being populated, when the shipment cost document is created.