I've just received my new Smart Hub to replace my current Home Hub 3. Currently, the dsl cable runs from the telephone socket to the white modem but there is no connection port available for this on the new Smart Hub.
Do I need to replace the master socket or get a RJ11 to RJ45 converter?
You don't need the modem with the smart hub. Just connect the rj11 from the phone socket to the dsl socket on the smart hub. You might want to hang on to your old hub and modem, the smart hub is not necessarily an upgrade.