Codecs can have many different settings. And it's not just codecs, there is also the container format, which also can have many different settings. There are thousands of possible combinations. Frankly, I'm amazed that OpenPLi plays nearly everything I throw at it.
If it can't/won't be fixed in OpenPLi (a STB is not a media player), I sometimes have success remuxing to a different container format. Remuxing doesn't re-encode the audio/video streams, it just puts them into a different container, and is therefore quite fast, and without quality loss.
I see! I know that an STB is not a multimedia player, it all started from the fact that on Zgemma H9.2HSE (with OpenPli) all multimedia files work while on uClan Ustym 4K they don't work.
Now uClan Ustym 4K with openpli-python3-ustym4kpro-20220418 many multimedia files work some don't work, but on H9.2HSE all multimedia files work.
Thanks to the work done by rantanplan