Hi, I've had the message 'insufficient signal strength' showing on my tv for 24hrs now and no picture at all.
got through to faults and they gave me a system update and reboot procedure:
Take power plug out of back of decoder
Hold down up arrow, ok button and power button all at once
Then put power plug back in the back of decoder while still holding all buttons
Once green arrow comes up on decoder you can let go of buttons and wait as it resets itself and updates software.