This is due to the better filters fitted to these newer units. This is due to the better filters that are fitted to these newer units. Simply insert Unstripped conductors and Close the Clip to connect.
DAVOX BT Openreach NTE5C MK2 Master Telephone Socket + MK4 Faceplate + Back Box
DAVOX BT Openreach NTE5C MK2 Master Telephone socket + MK4 Faceplate + Back Box
DAVOX BT Openreach NTE5C MK2 Master Telephone Socket + MK4 Faceplate
BT Openreach NTE5C Master Socket MK4 VDSL Faceplate + Box/BT 2/3A Slave Socket
