When I press the home button on my remote I get sound but to picture. I have tried turning off the power to the SkyQ box, holding down the standby button to start a sore ware update, have changed the hdmi cable. Nothing works. Online instructions mention instructions on screen but as my screen is blank I cannot see settings etc. I have tried pressing home, 1,0,8,0,home as suggested when there is no picture. Can anyone help?