@Prinzzzlutz hello, as a first step, could you please detail your setup?

storage peripherals connected case Recalbox version method used to flash recalbox is it a fresh install or an update? screen (resolution, connection between pi and screen) power plug anything else you think is relevant

Then, could you please link your pi to the network using an ethernet RJ45 cable and provide a support archive ?
https://wiki.recalbox.com/en/tutorials/troubleshooting-information/support-script

Thank you