If you have a decent player in your LAN, most of the time you won’t transcode. But, if your local player doesn’t support the video or audio codec of that file, then your player will ask the server to transcode the file. Transcoding on LAN is common for example when your audio is Atmos or TrueHD.
If you disable transcoding (it’s a global configuration), you on your LAN and remote clients will just get a generic error message, and your friends will start texting you saying that they are having problems playing certain titles. Trust me, it only causes headaches.
You have to choose: Save bandwidth: reduce remote stream and enable transcode as they told you to Save CPU/GPU Power: don’t touch the remote stream and ask your friends to increase the remote bandwidth on their clients.
I have a Roku Ultra. It deals with everything I have (I create it all), but it vomits on ASS subs. I have to tick the box that tells Plex NOT to transcode any subs, except Image based subs, then ASS will work on my Rokus, but Plex has to ‘Remux’ the video and audio stream into HLS in order to play the ASS subs without a full blown transcode of the video stream.
That ‘Remux’ is a transcode. If I had the transcoder off - my ass subs simply wouldn’t work.
I have some Roku Ultras out in the wild at friends and family’s homes and sometimes they’ll need an audio transcode only. If the transcoder was off they’d get no sound.
Ya gotta have the transcoder. It does things you need when you least expect it.
