PLEx server on Synology NAS - Audio not playing on some mkvs in Apple TV 4k

I would like to point out that on MediaInfo the file says has 3 audio channels:

https://d.pr/i/doCUib

And one more important think I missed:

My files are on the cloud, and linked through Rclone… If i put that files on a local library, then Plex Server reproduce them perfecly… Any explanation to that behavior ?

Thanks for your answer. I was thinking to do the “Plex dance” (i know it), but I Though maybe could be another option.
I will inform about that in 1 day or 2, sure !

THANKS !