TCP Connection dropp and packet loss

I am experimenting with docker on Windows Server 2016 and having some strange problems with TCP connections.
After container receive some average load of traffic tcp connections start to get dropped.
I have also tried debugging the traffic with HTTP Web API calls and what happens is strange.
On the side of the container data is received and served back to the caller but the caller (e.g web browser) never receives any data.

The system running docker have a static IP and container is bound to address so there is no NAT in between.

Any ideas ?