RDS Gateway 90 second delay

Hi

I have a problem similar to the post below. I've tried the solution provided, but it doesn't help.

http://social.technet.microsoft.com/Forums/windowsserver/en-US/bb2b8804-d68d-4951-b90b-e2aa9355ca68/rds-gateway-60-second-delay?forum=winserverTS

I have a single Windows 2012 R2 RDS server, which acts as all the RDS roles, including RD Gateway.

When clients connect through the gateway, sometimes connections experience a 90 second delay while 'Configuring Remote Session'. This doesn't always happen though, it seems random.

In the event log of the RDS server, I can see this - and it's always at the same point between two 261 events and always 90 seconds.

So for example:

10:16:26 - Event 261 TerminalServices-RemoteConnectionManager - "Listener RDP-Tcp received a connection"

10:17:56 - Event 261 TerminalServices-RemoteConnectionManager - "Listener RDP-Tcp received a connection"

Any thoughts?

Thanks

Andrew