Fortnite 4: 3 problems?

Hey and I play fortnite on 4: 3 (1400x1080) everything is fine but if I want to Raustabben eg change the music or so it is suddenly gone and then play back to normal 16: 9, can you help me?

Since you play in 4: 3, you realize that you do not understand much about copts. You see in the settings what changes, or you can't see them because they are in your missing pixels.

Kul hara