Song Loads but will not play in DEX / Red Mobile

This would indicate that you have not set a correct sound card configuration in Menu or options->options->in / out page. Make sure that you select the correct driver, output mode, and sound card or Asio channel outs for the card that is connected. If this configuration is not correct The decks will not move as it cannot connect to a setting that you have specified. Many times this happens when you use a different sound card for your gig and you are now at home using the machine onboard sound card. The software will keep the configuration that was last selected. It will not automatically switch so you need to manually change the settings.