If you are having issues sending or receiving a fax due to possible interference on the telephone line or if you are using a VoIP system, we recommend changing the modem speed to minimise errors in fax operations.

1. Press (Settings) > All Settings > Initial Setup > Compatibility.
    
2. Press the option you want.
    
   • Basic(for VoIP) reduces the modem speed to 9,600 bps and turns off color fax receiving(*) and Error Correction Mode (ECM), except for color fax-sending(*). Unless interference is a recurring issue on your telephone line, you may prefer use it only when needed. 
     To improve compatibility with most VoIP services, Brother recommends changing the compatibility setting to Basic(for VoIP).
     *: Available only for Brother machines with color fax function
      
   • Normal sets the modem speed at 14,400 bps.
      
   • High set the modem speed at 33,600 bps.
3. Press (Home).