I have three quad FXS cards (in slots 1-3) and one quad FXO card in slot 4. I have a few telephone sets connected to the FXS cards, and * allows calling from one phone to another and from phone to console, etc. Diax also works. I have a CO line connected to one circuit of the the FXO card. When I dial from the console, the busy light on the FXO card comes on, but it doesn't break dial tone. When I put an Adtran FXS circuit in tone test mode, I can detect the tone at the punch-down block. When I put the FXO circuit in tone test mode and dial a local call, I hear the tone from *. However, I can't hear the tone at the punch-down block (and it hasn't broken dial tone.) The Adtran has been set to factory defaults (loop start, etc.) Is there something I'm missing here? Must the FXO cards occupy lower slots than FXS cards? Would the CO line originating at a pair-gain system (SLIC96?) require a different interface? TIA Mike