Solved! Go to Solution.
If you have a home hub 5, you do not need the white Openreach modem. Simply connect the DSL input of the home hub 5 into the master socket, instead of the white modem.
The white Openrach modems or their power units, do fail.
Are you using just the hh5 with the modem cable which is connected to master socket connected to the hub DSL socket and not the wan socket. If you use the modem then the modem cable is connected from the master to the modem and then the Ethernet cable from the modem to the hh5 wan socket
So what is connected to the modem?
if using modem cable from the the master to hub DSL socket then you should not be connecting anything to wan socket
your hub 5 should be connected like this you no longer need the openreach modem with the hub 5