Problem with Zoom USB modem

I am trying to set up Hylafax on a Ubuntu 14.04LTS machine.
I get it all set up and I start getting wedged e-mails.
I set the server tracing to 0xFFF and when I look at the logs, I get the
following:

FaxGetty[1450]: DELAY 10 ms
FaxGetty[1450]: MODEM flush i/o
FaxGetty[1450]: <-- [4:ATZ\r]
FaxGetty[1450]: --> [5:ERROR]
FaxGetty[1450]: MODEM Command error
FaxGetty[1450]: MODEM set DTR OFF
FaxGetty[1450]: Unable to setup modem on /dev/ttyACM0; giving up after 2
attempts
FaxQueuer[1396]: MODEM /dev/ttyACM0 appears to be wedged
FaxQueuer[1396]: MODEM WEDGED: bin/wedged "ttyACM0" "/dev/ttyACM0"
FaxGetty[1450]: CLOSE /dev/ttyACM0

Why would it error out on a reset command? I tried cu to test the modem, AT
command gives OK, but ATZ, ATZ0, and ATZ1 all error out.

This is a model 3095 USB modem from Zoom (based on Conextant chipset *I
believe*)

Any ideas?

Thank you in advance
David