I am using a Micca digital media player and flash drive for a video with an Epson EX 7230 video projector. I want to hook up headphones. We tried using the proper cable (male to female etc) but no sound comes out. Do I need to download some software? Is there another easy way to do this? I have an exhibition and want to only work with the headphones, not the Epson unit sound, if possible.