FAXing From A QEMU KVM

I have an EPSON WF-3520 All-In-One printer.

My host OS is Ubuntu 14.04. I have a QEMU/KVM VM Windows 7. I can print documents from the VM to the printer just fine.
However when I try to FAX something, I get:

"The printer port is invalid. Check the port setting."

I can fax directly from the printer just fine also.

Am I missing a setting somewhere in the VM?

Thanks,

Ray