Printer Does Not Switch Automatically Between Voice and Fax Calls
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Check Is the receive mode set to Fax only mode?
If Fax only mode is selected for Fax menu > Receive mode set., there will be no automatic switching between voice and fax calls.
Set the receive mode to Tel. priority mode, DRPD*1, or Network switch*2.
If the receive mode is Tel. priority mode and an answering device is connected to the printer, check whether a proper message is played back when the answering device answers.
*1 This setting is available only in the US and Canada.
*2 This setting may not be available depending on the country or region of purchase.