Samsung UN60ES7500FXZA - Manual (Page 197)

N If you turn the TV off while watching
in the PIP mode, the PIP function is
reset to Off . When you turn your TV
on, you must turn PIP on again to
watch in the PIP mode.
N You may notice that the picture in
the PIP screen becomes slightly
unnatural when you use the main
screen to view a game or karaoke.
N The PIP is not supported in 3D
function.