Without providing diagnostic data in the form of logs, your argument doesn't help

[Chillbo]

Buffering issues with 4k File

just for report osmc@osmc:~$ iperf -R -c 192.168.0.20 Client connecting to 192.168.0.20, TCP port 5001 TCP window size: 85.0 KByte (default) [ 3] local 192.168.0.54 port 38351 connected with 192.168.0.20 port 5001 [ ID] Interval Transfer Bandwidth [ 3] 0.0-10.1 sec 115 MBytes 96.2 Mbits/sec Vero4k has a good 100Mbit ethernet (router and cable are gigabit ready) and enought for any standard 4k video BHH