The company I work for is based in Australia as is the payment gateway (SecurePay).
We are seeing a very high incidence of credit cards being declined for reasons other than the usual 'lack of funds, card expired, etc...' ones. The message I get is 'do not honor'.
Most of our customers are in the US and using corporate cards. Could the latter be part of the problem - policies in place to block online transactions with non-US entities?
A solution would be to plug into out US based gateway (which we use to manually process declined transactions) but I'm hoping that the fix is easier than having to update our ecommerce platform.