I am trying to watch MP3 movies on a screen via Inspirion laptop connecting it to my Epson projector to project image on screen via hdmi cable. However, my Bose external speakers plugged into the audio of the laptop don't work and will only work when I pull out the hdmi cables, but then the movies don't project onto the screen any more. It worked at one point a few weeks ago, now it doesn;t work. Anyone can suggest a fix?