Version 1.0 September 2014Page | 122ScreenProblem Possible SolutionsNothing is displayed on the LCDscreen while using the phone.Check that the phone cables are properly connectedto the ports. (Please refer to the section on ‘PhoneInstallation’ under ‘Preparations’ in this user manual.)GeneralProblem Possible SolutionsNo ringtone is heard or theringtone is too soft.Press the [Volume] button to turn up the ringtonevolume. (Please refer to the ‘Volume Control’ sectionunder ‘Basic Functions’ in this user manual.)The voice is unclear due tointerference or crossed lines.If you are using the speaker, try using the handset.There is too much echo whenusing the speaker phonefeature.When you broadcast, the speaker sound may echo.Maintain a distance of 1m from the phone.Caller ID does not appear onthe LCD screen.- Ask the service provider whether the caller IDservice is activated.- Caller ID will not appear on the screen if the callerhas requested the telecommunication serviceprovider to hide their number.- If the user is calling from an area where the caller IDservice is not available (e.g. international calls),caller ID will not appear on the screen.- If the user calls from a payphone, caller ID will notappear on the screen.- If the caller information received from the serviceprovider is invalid, caller ID will not appear on thescreen.- If the service provider does not send callerinformation, caller ID will not appear on the screen.Main Menu cannot be accessedfrom the Call Forwarding orDND screen.Put the UC dial in the center position to use themenu.