How to watch a movie when tv is attached outside?

[prindle]

I own a rockwood mini lite 2504s with a IRV33 multimedia system. I can attach the tv to the outside of the camper but it only has a coaxial cable on the outside. I bought a separate bluray player to attach to the tv but then I found there is no sound still on the furrion tv. I was wondering if there is a way to get sound either on the tv or connect to the IRV33 to play the sound. If not I will just go buy another sound bar.