Fax TX Line Auto Select Adjustment
You can set whether to automatically select the fax line instead of using the line registered to the recipient, when sending a fax to a destination obtained from a remote address book.
1.
Press 
(Settings/Registration).
(Settings/Registration).2.
Press [Set Destination] → [Acquire Remote Address Book] → [Fax TX Line Auto Select Adjustment].
3.
Press [On] → [OK].
Select [Off] if you do not want to automatically select adjustment for Fax TX Line.