How can I get the AC3 passthrough (in spdif) to work? In video players(kaffeine, vlc...) I have tried to enable the passthrough option, but there is no kind of sound coming out. There is sound coming out only in stereo mode.

Can there be problems with the ALSA? My sound card is ingrated to Asus K8N4-E Deluxe(nForce4) motherboard and I use Suse 10 distro.

You have to make sure ALSA is used instead of oss. Next make sure the output device is either spdif or iec958. This is far I can go because I do not have the equipment to convert spdif or iec958 to analog. My sound card's, Audiotrak Prodigy 7.1, spdif or iec958 output is hw:0,1 because hw:0,0 and hw:0,2 are front, rear, center, sides, and subwoofer.

A good howto is at http://gentoo-wiki.com/HOWTO_Dolby_D...t_(AC3,_SPDIF).

The USE flags are compile options that can be passed to the configure utility. If you installed mplayer or kaffeine (xine-lib) through an rpm, deb, or other packaged based form, AC3 or DTS may not be included.

I tried those commands in the link and there's no sound.