Movies and Chill in cabin?

[Jennsails]

We are sailing on a 5 day itinerary on the Sky next week. Being a smaller ship there does not appear to be as much extra stuff to do on board. Either way, when we cruise, sometimes we just like to chill in our cabin in the evenings as we are not night owls and take our cruises to relax and enjoy the ocean. Last time we cruised, we tried to hook up an HDMI cable to watch downloaded movies and shows through the cabin tv and no luck. We had to watch on our laptop. Does anyone have any tips of any cables etc which we should bring to hopefully be able to chill and watch our own downloaded content on the cabin tv? I know the in-cabin entertainment lacks options; I think like 4 channels and a few PPV movies. I also know that the shows, parties etc are great and all but on a 5 night itinerary some night we just want to avoid crowds, order room service and enjoy our space. 

Thank you!