I need a external soundcard supporting dolby digital

[Arfus]

Is there any exeternal soundcards for macs tahat support Dolby Digital?

 

[andrewheard]

You sure you need an external one? Most Macs have optical digital out (just need a mini-jack to toslink adapter) and you can do Dolby Digital passthrough for DVDs and movies/shows if you use Plex for playback. There are other apps available too.