Error during/after rendering, video seems OK

Hi all, when I render my project to an mp4 file I always get the same error:

> Started render process: C:/Program Files/kdenlive/bin/melt.exe -progress C:/Users/mozzie/AppData/Local/Temp/kdenlive-ChspXw.mlt
> …
> [mp4 @ 0000024f126d6640] Timestamps are unset in a packet for stream 1. This is deprecated and will stop working in the future. Fix your code to set the timestamps properly [mp4 @ 0000024f126d6640] Encoder did not produce proper pts, making some up.Rendering of x.mp4 aborted, resulting video will probably be corrupted.

The video seems OK and runs fine, so this is not a big problem. I’d just want to know if anyone as seen this and if there is a fix. Wrong settings somewhere?
I’m using kdenlive 23.04.0-1 on Windows 10.