How to play a movie through my Surface Pro 3's HDMI out port

How do I tell Windows Media Player to play on the screen connected to my HDMI port?

My TV (a 5 year old Samsung 46") won't let me select the HDMI port (#3) until it detects there's a signal on it and for some reason, my Surface won't recognize the external monitor.

It's almost like a chicken and egg situation.

The TV has 3 HDMI ports. One is connected to a PlayStation 3 which works as expected.

Any help would be appreciated.

Thanks.