I've got a C-Class with 2 CO lines, the second is also used for a fax line. Everything was working fine until the customer replaced the multifunction fax/printer with a new one. The fax calls get sent to the fax machine as required, but the fax machine will not answer. All settings are correct including auto answer. If I pull the line from the switch and send all calls directly to the fax machine, it picks up and works great.

Ideas?

The energy level probably needs to be adjusted.