gateway error code E00051 out of the blue now on EVERY C/C sale

We've ran magento now for several years and always with authorize.net

All the sudden (no changes on our end) we're getting a gateway error code E00051 error on every c/c sale we run. Paypal comes through fine. The customer can put the order in but as soon as we go to invoice it on our back end within magento we get "Gateway error code E00051: The original transaction was not issued for this payment profile."

So we have to run to authorize.net and manually enter the sale in the virtual terminal and finish the process.

The basic error from a google search comes up with the address and info not matching the original auth but it does match and again it's happening on every single transaction one after another.

Of course we're a music store in our biggest 30 days of the year as well... grrr

Sure appreciate any help you can give.

Dave

http://dcmusicstore.com

I contacted authorize.net and they said they need the "full response string we are receiving back" to help diagnose.

How would I get this?

Thanks,
Dave

Site is http://dcmusicstore.com