Picture Slideshow Screensaver not loading image on every second boot.

I'm trying to use a Raspberry Pi 3B with LibreElec for the single use of displaying one defined image after boot for digital signage.

So I'm using the Addon Picture Slideshow Screensaver. I saved the image on the SD card and added the path to it in PSS.
But around every second boot the screensaver is just displaying a loading circle that stays forever. If I then press a button to end it and wait for the next run after 1 minute, it usually works. But the system has to load the image reliably after every boot.

Any ideas?

I used another approach with Raspberry Pi OS and feh instead.