I have bought a GoodmansGDR11 free view box for my Matsui 1407RS, but after connection the welcome screen hasn't appeared. Eventually by mistake on the screen appeared pin code screen & no longer I could have enter the tv's menu through its remote control. I have found an advice to type 3 times the wrong code & then to press tv Vol+ button together with digit 7 on the remote. But even this doesn't work. Does it mean the whole tv has to go through professional tuning?