Anologue Fax on 2.8

Can someone tell me if these are the correct steps or what the correct steps are to have analogue faxing working on my 2.8 with asterisk 1.4.21 system.

I created a zap extension for the fax. In the extension setup I did not enable fax receiving on this extension as there is a fax machine attached. On my inbound route I select detect fax and have chosen zaptel for detection. In the fax destination I chose extensions and the one with the fax machine on it. My sangoma card is setup to detect faxes.

So far so good… Call comes in, fax is detected, sent to fax extension, fax machine answers… But the fax always fails. Out bound never works either.

The calls are in and out on a pots line, so it sounds fairly simple. Have tried with ecm on and off. So, this seems very straight forward… Is there something that I am missing that may be stopping the fax machine to properly hear the signal? Did I set something up wrong?

I have two systems identical, and I cannot get either of them to work correctly. Just looking to see if anyone has some tips or tricks.