I’ve been fighting this battle for ages, keep adding speed to my system only to have some 4K movies buffer. I have an iMac-based server (3.6 GHz 8-Core Intel Core i9) connected to a fast mesh Linksys Velops WiFI feeding an Apple TV 4K which in turn is going to a LG C9. My media is stored on a DS920+ (base, no SSD cache)
To take the wifi out of the equation, tonight I ran ethernet from my switch (where the iMac is connected) directly to the ATV4K. Speed test is showing 500 Mbps coming via the internet, so my network is clearly not the pinch-point.
Not being that savvy with Plex or networking, I’ve run out of things to check and looking for ideas. Whole point of buying the LG and the ATV4K was so I could stream movies with quality, and my system keeps struggling. I’m getting frustrated not knowing where to look.
Your internet download speed has no effect when it comes to streaming media inside your home network.
The internet download speed will only be a relevant factor if you’re streaming content from a remote server.
The iMac, Apple TV and Syno should all have a Gigabit LAN port. Can you verify the LAN port types of the other network components in your setup (they should be 100 Mbps or 1 Gbps; some routers support Gigabit speeds but only on a subset of their ports or require a configuration to activate it).
When it comes to network speeds, it’s all about identifying the „weakest link“ and the maximum required bandwidth.
What’s the Bitrate of the movie you’re trying to stream (Get Info > View XML → Required Bandwidth)?
In addition… what information is showing in the “now playing” tile for that playback on the Plex server dashboard? Maybe you could share a screenshot.
Specifically:
is the stream listed as local, remote or indirect?
All of my hardware (iMac, NAS< switch, AppleTV) are gigabit or better. Yes, internet download speed is not entirely relevant, but I believe it shows that my switch and ATV4K are up to the task
I’m testing with various bitrates from 99Mbps to 60 MBps.
Because I have the speed that I have, I’ve configured Plex to direct play so (as I understand Plex) transcoding should only be an issue if subtitles are being added and therefore burned it at play time
I wonder if the TV (LG C9) might be limiting factor here…it has three means of getting data, WiFi, ethernet (I have it hardwired to a Velop child node as well as WiFi), and via the HDCMI connection to the ATV (the latter is the one that’s a factor I’m using the ATV4K Plex app, not the LG one).
Harry Potter 25Mbps…buffering (not badly but still)
Dune 2 17Mbps…stuttering badly
Moonshot. This one’s a whopping 70Mbps and buffering as one would expect. Also direct play.
Note that for this and one of the ones above (I think Dune 2) I got a message one the screen that my connection to the server was too slow to show this content. I fail to see how when I have gigabit connections throughout and the DS920+ is anecdotally reported to sufficient capability for multiple 4K streams
