TCP Out of Order Problem

[doghead]

We are using openvpn to link two offices for a product demonstration for video streaming. We need to have this run using TAP as we want to have full network discovery using LLDP, CDP, etc.

We are using Mikrotik routers, one as server and one as client. The link works great and we get good throughput under normal conditions. The uplink speed of the client end is 3Mbps and we run tests with iPerf showing we get 2.97Mbps of throughput.

However, when we run video, we run into a weird problem. Using RTP/RTSP streaming, every 50-100 frames we get an error saying of TCP Out of Order. This is followed by a restart of of the stream.

We think that we are having an issue in route variation over the public internet that causes frames to arrive out of sequence. Is there anything you can do to assure packet ordering through a tunnel like this? Is there some buffering mechinism that can be adjusted.

We can share full configuration, but I am just looking for where to start.

[doghead]

Anyone have some suggestions on this?