I have a UE55MU6470 and have a Humax connected in HDMI 1.This box is only used to record programmes.
While I,m watching Live TV all is well but when to 'Source' and choose, thru the Menu at bottom of screen, Humax the picture is blew up.The only way to fix this is to go along the menu and Choose say I-player..enter that .leave that app and go back to Humax and the picture now is normal.
On TV setting Pitcure Size Setting is greyed out and picture settings within the Humax is 16.9 and Display Format is set to Auto.
Also the same happens when I choose the next Source which is an Amazon Fire Stick.Similar method to normalise this picture is the same.
So I think it is a setting within the TV. but struggling to find it.
Think I have found this out.On TV menu I went to Universal Remote and clicked on Humax.Then chose Quick Channel Change and set that to Fast. Maybe doing that has an effect on HDMI.. Also on TV whatever setting I corrected Picture Size is now showing so have set this to 16:9 Standard and Fit to Screen is Auto. Anyhow I,ll monitor and see if this solves the problem.
No..this has come back because I have connected a new Manhattan Freeview Box.This is connected via HDMI 1 on TV but still when I choose this or the Firestick(HDMI 2) the picture is All Blown up in size. Again within Settings on TV Picture Size is greyed out!