Remote live tv buffers every few seconds

[yakfod]

Server Version#: 1.41.7.9717 (linux, docker)
Player Version#: iOS 18.4 latest
Tuner Make/Model: hdhomerun flex 4k

I have latest plex server running in a docker (linuxserver.io) container on ubuntu server 24lts in a mini N100 machine. Everything works locally direct played or hw transcoded. Remote streaming non-live content similarly works as expected, limited by the clients bandwidth as the uplink is 1 Gb fiber. Live TV also works just fine locally direct played or hw transcoded. I tell you this to set a baseline that I think things are set up well.

But no matter what, remote live TV buffers every 2-3 seconds even if transcoded to 4 Mb 720p. This can be my iphone 15 pro on 5G/LTE with a >100Mb/s downlink, same iphone on good outside wifi, or TV apps on remote internet connections.

I know I have the uplink and hesitate to blame peering as non-live content streamsq fine. I know the N100 can hw transcode fast enough to keep up (I’ve seen 8-9x transcode speeds to 720p).

If I VPN into my network on same phone and 5G/LTE connection, plex sees the connection as local and live TV streams fine.

I’m not smart enough to figure this out. A few thoughts:

1. I don’t think I’m getting throttled as I’m using a non standard port, plex is using secure connections, and non-live content streams fine.
2. Non-live content streams remotely fine without VPN, so my port forwarding, uplink, client downlink are all OK.
3. Standard pihole/pivpn setup without unbound shouldn’t require any plex specific setup, right? I have the local address of this hardware in the allowed without auth list.
4. I saw this post from a few months ago which seems pretty similar to my issue, except turning off hardware transcoding does not help me.
   Live TV buffers remotely, but OK on local network
5. What is different between local and remote streaming if all other variables are unchanged? DNS?

Yes, I can just use the VPN. But I shouldn’t need to and want to try to understand what’s happening. Appreciate you taking the time to read my wall of text and any thoughts you may have.

[yakfod]

So I downgraded the server to 1.41.6.9685 and my iphone app simultaneously updated to the new version 25.15.0 (1053). I apologize for confounding the data here.

Remote streaming live TV no longer seems to buffer repeatedly and appears to utilize available bandwidth as expected without a need to VPN to local network, however if it transcodes the stream I get no audio. Either the new app is not handling opus or the server is doing something weird with audio transcoding. If I direct stream, I can see through the dashboard that the app is getting AC3, and I get audio. If I transcode to 720p it converts the AC3 to either multi channel or stereo opus and I get nothing.

I realize this is a work in progress, just documenting my findings.