I like music and good sound from the movies I watch. I removed the original unit and replaced it with a Denon 5.1 AVR receiver and have a 12" powered sub in the cabinet. Replaced the 4 original ceiling mounted speakers with smaller but better quality speakers. The Denon unit has Audessey which corrects the acoustic problems of the interior of your trailer, resulting in a very nice listening room. I use a Blu Ray player and hook the player to the AVR with HDMI and then to the TV with HDMI also.
Not the setup for everyone, and it does require 110V AC electricity, but then so does my TV.