1. Connect computer to 5.1 channel speaker. If speaker is with 3.5mm stereo audio input interface, you need three 3.5mm stereo connecting audio cable; If audio input for RCA lotus connector, you will need 3 3.5mm lotus connector connecting cable. Install the sound card to the computer and install drive, and then connect the audio cable to computer to use. 2. Set Final codec as "S/PDIF OUTPUT", turn on sound card "S.PDIF" and play. (This final decoding setting is just common set. You can select the recoding DD5.1 output such others options in different case.