Solved Aspect Ratio Problem with PSX (Retroarch) on RPI3 Recalbox 01.12.17

[Backpaddle]

Since the first day, i have the problem that the screen aspect ratio is fixed at 4/3, with Magic Key + X i can get in the Retroarchmenu and choose 16/9 for my TV.
But when i close the game and restart it, i got 4/3 instead of the 16/9. I try to manual change it via a .cfg in the recalbox.cfg or the pcsx-rearmed.cfg (didnt find the retroarch config itself).
Dont know what i can do more, it is a little problem but it make me sick.
btw. i use the sd card + usb stick solution.

[Xanarkan]

Normally you can choose directly from EmulationStation -> start -> game settings -> games aspect ratio.

[Backpaddle]

@xanarkan yes, but it didn´t save this, i must do this everytime i start a game.
But i found a fix by myself. I fix the resolution and aspect ratio in the configs and edit that the ratio is not given from the core.