An update from our problems at a site with the same problem.... after doing our traces with both cards it was determined that something with the signal sent from the telco just wouldn't work with the combo card. I would take as many trace's that you can with the the combo card and with the old style card, which you will have to probably get as a refurb. If you are like me you won't see a rhyme or reason for the issues but trace it and make it fail over and over and over some more. Vodavi finally got enough info from the traces to say "yep the combo just won't work with the signaling from the telco". But throw as much info at them that you can.
