VIDEO NOT PLAYED ON SAMSUNG TV

Hello everyone, I'm new to the forum.
I installed Serviio on the PC that acts as a server.
Connected to the usual PC network I have 2 Samsung TVs on the network.
I shared a video in .mkv format and the strange thing is that one TV plays it and the other doesn't...
If I play the same file with an external USB connected to the TVs it doesn't play on either of the 2...
The TV where it plays perfectly via Serviio is a Samsung UE49KU6100.
The TV where it doesn't play, among other things, a more recent TV than the other is a Samsung UE43TU8070U.
I can't explain this thing... didn't the codecs pass through Serviio?

[atc98092]

Remember that an MKV is simply a container, and in fact this container will hold any available audio/video codecs. It's possible the media you have uses codecs that your TV doesn't support. Without knowing the contents of your container, we really can't say why it won't play. See the link in my sig line for determining the contents of your file.

Hi I solved it. On the TV that wasn't working the transcoding preference wasn't set as Samsung J series