HDCP error, however, is very common with now TV boxes. Try using a different HDMI cable and directly connect it to your TV, skipping the AV amp. Cut power to now TV box, switch on TV, switch input to HDMI, then turn on now TV box. If it still does not work, try the other HDMI ports of the TV.
If you're already using a direct connection, then do the opposite - connect it through AV amp.