Don't realy know but you should have had an answer by now if anyone could help,but in saying that try going into MENU on remote and see if you have selected a function that allows you to switch off by pressing any key (press any key to continue springs to mind)look for power settings/stand by settings that sort of thing,the answer might be there somewhere.You have nothing to loose just repost the questio again if you can't find anything in SETTINGS,good luck.
anon, July 2016