On the Pioneer AV receivers, to use the 5.1 selection, you have to have it wired with the individual 5.1 configuration. On the back of your receiver there are 6 RCA ins for this set up. If you DVD player supports this with the proper outs, your in business. If your are using (what most people will do) coax or fiber optic set up, you don't use the digital 5.1 selection. You have two other selections. One gives control to your source and will give 5.1 Dolby Digital II or DTS (or any other format your receiver supports). The other selection is for the various equalized formats, i.e. "Adv-Movie", "Adv-Music", etc. I hope this helps.