ITUNES BECOMES UNAVAILABLE

SELECT MY FILM, IT COMMENCES AND AT 8MINS 50 SECONDS, THEN 17 MINS, THEN 24 MINS THE FILM STOPS AND THE MESSAGE ITUNES IS UNAVAILABLE PLEASE TRY AGAIN LATER APPEARS ON THE SCREEN, I HAVE TO GO BACK TO THE MENU RESELECT FILM AND IT PICKS UP FROM WHERE LEFT OFF, ONCE IT IS PAST 30 MINS IT IS FINE, IS THIS ANYTHING TO DO WITH INTERNET CONNECTION SPEED? THE APPLE TV SOFTWARE IS ALL UP TO DATE, THIS HAS ONLY STARTED IN THE LAST TWO MONTHS AND IS VERY FRUSTRATING