multiple WCF services hosted in WAS IIS using netTcp protocols on same port issue

Question

One of the services works fine but the other always throws a Socket Timeout 'forcibly closed' error.

I have portSharingEnabled='true' on both services and the netTcp Port Sharing windows service switched on.

I've done a lot of research on this but am unable to find the cause, any suggestions?

It's not an option to change the port either due to legacy system setup.

Each netTcp Binding looks liks this:

8033:*

Is that right or is the * the issue here? I've run out of ideas as you can tell.

Last point: It definitely isn't a timeout issue as I get the error on the client side instantly each time. All other binding config values are matched on both server/client side and set close to max as suggested by other similar issues here on SO.