highly recommend you use your TV's 16:9 mode most of the time.
NNIf you have set Double (à, Œ) mode in PIP
Auto Wide: Automatically adjusts the picture size to the 16:9 aspect ratios.
16:9: Adjusts the picture size to 16:9 for DVDs or wide broadcasting.
Wide Zoom: Magnifies the picture size more than 4:3.