To enjoy the 5.1 channel speaker quality fully, your DVD titles and CDs must support 5.1 channels.
Enabling S/PDIF on the DVD Program
When using 5.1 channel speakers, you will need to install the “Power DVD” program on the DVD Installation CD (supplied Separately) and then set it up as described below:
1.Run the “Power DVD” program and click the settings button., the configurations window pops up.
Settings Button 
2.On the “Audio tab”, change the Audio Output Interface setting to “Use S/PDIF Output”.
Audio Output Interface
3.You are ready to enjoy your home theater system with your own DVD’s.• If you have enabled S/PDIF in the DVD program, the computer speakers and headphone are not functional.
• To control the sound volume on your 5.1 channel speaker system, use the control on the digital amplifier. (Please refer to the speaker manual.)
34 Users Manual