Apple TV shows spinning wheel when trying to play movies

Apple TV Spinning Wheel

On Apple TV (Gen 2 or 3, not too sure) I can see my iMac, I can see Home Movies, I can see image previews and the list of movies I have on the TV.

What I cannot do is play them, it just gives me the spinning wheel.

I've reset set back to the beginning.

Not too sure what the problem is, suspect its something to do with the network but no idea how to test or fix it.

Anyone got any bright ideas?

L