Inconsistent playback of 4k UHD across devices and apps

[fuelraccoon12]

Findings below. Behavior still persists. iOS Swiftfin with Native Player showed new behavior -- video stuck for a couple seconds then rapidly caught up. Audio persisted without error throughout. Tested again with worsening behavior.

This was tested with my original file, NOT against the ffmpeg remux. Should I test with that file as well, or rerun the command with the new ffmpeg version?

PC - Brave Browser - Direct Streaming
Still Present, same spot.
Log: https://pastebin.com/pWaC9GA0

PC - FIrefox - Transcoding
Clean play
The media is being converted into a format that is compatible with the device that is playing the media.
Framerate: 195fps
45.9 Mbps MP4 H264 AAC
Reason for transcoding
The container is not supported
The audio codec is not supported
The video's range type is not supported
Log: https://pastebin.com/YPnsYXLC

iOS Swiftfin Player - Direct Playing
Clean play
(No log)

iOS Swiftfin Player Native - Direct Streaming
Still Present, exact same spot. New Behavior - ~:20 second mark, video stuck for multiple seconds, then caught up at end. Audio persisted without error throughout.
Log: https://pastebin.com/eJgVDTR2

2nd play - Video started, skipped ahead few seconds, lost sound, lost video, returned seconds later audio and video considerably out of sync (~1:12 mark).

[fuelraccoon12]

Server log file: https://pastebin.com/rDn8t6bm

[fuelraccoon12]

Adding more data to review: Went and installed Plex Media Server and played same file through Plex Web Browser and the Plex iOS app, both play just fine. Plex iOS app player info says Direct Play. Is any of this narrowing down troubleshooting? (Direct Streaming?)

[gnattu]

No it does not help at all. It is the same as "but it plays in VLC". It does not provide any valuable information at all.