I recently upgraded my soundcard with Audigy 2 ZS. The installation process went fine. The sound is great when using Creative's MediaSource audio player. The issue is when using other media players i.e. WMP, Real, WINDVD6, etc. I have a 4.1 speaker configuration. After upgrading my other media players only recognize a 2.1 option. I have everything set properly in the control panel and in the Creative control panel, in that I indicated my speaker config is 4.1. I cannot determine the source of the porblem. My media players will not let me select the 4.1 option. Hence I here sound only from 2 channels, which sucks for DVDs.

Any ideas?

Can you try downloading WinDVD Tweaker, that should allow to to force 4 channel output in WinDVD.