Hi, yesterday I connected an external aerial to my 5 year old KDL40S2010, to see if I can get freeview. After I disconnected the aerial the TV now turns itself off and then back on again approx every 10 seconds whilst making a clicking noise from the back of the set. I have tried unplugging the set from the mains (overnight) but its still the same. there are no lights flashing on the front of the set. Can anyone help please.