Dan, first of all, there is no "composite audio", it's composite video, the yellow jacks. You want the red and white jacks.
That aside, be sure the jacks on the TV you're using are indeed
outputs, and not inputs. Usually, the audio inputs are grouped with a composite video input, and the audio outputs are without a corresponding video jack.
Also, it may be that there is a speaker on-off switch that must be off for the audio outputs to have audio on them. I suggest exlporing the menus on the TV for possible output configurations. Check the owner's manual, too.
Larry
www.fineelectricco.com