Why does my 4k content buffer?

Hi guys

Just a quick question to try and identify where the issue is…

I’ve got an ‘okay’ plex server - the CPU passmark is around 6600, and i am playing Plex Media Player from the same machine - it runs 40-45mbps Blu Ray files perfectly with no hitches (on direct play)

I have a couple of 70-80mpbs 4k files that buffer constantly - the files Direct Play, so does that rule out the CPU as there is no transcoding? I’m using a wired ethernet connection so I don’t think it’s my network…

What could the issue be?

Thanks

If PMS is reporting DirectPlay, you have a network / communications issue.

At that bit rate for video, don’t forget to add the extra bit rate of the audio and then the overhead of TCP & IP to it.
Most televisions have 100 Mbps ethernet connections.

At 80 Mbps, you’re transmitting 10 Mbps just for the video (without overhead).
As a test, set your laptop / desktop at 100 Mpbs LAN speed and download the same file .
See what throughput you get. This is the best approximation you can get of what the TV is actually receiving.

TCP/IP has effectively an 80/85% efficacy. You’re on the edge with 80 but well under it at 45-45.

As a personal note: Playing 60 Mbps 4K over wifi is no difficulty for my television.

In the post OP indicated PMS and PMP is on the same machine, but then talks about wired network. Please clarify @Lozkin.