DTS encoding, is when the card encodes your audio for output to a recevier. DTS-Decoding is when the card decodes DTS-audio from the card inputs. The Prelude does not decode from inputs and never has. It will decode through software -such as when you are playing a DTS-encoded disk...
My understanding was DTS Encoding is like DDL. It encodes your analog signal into a digital for transport over Optical out.
The prelude could always play a DolbyDigital encoded disk but couldn't encode it until DDL functunality was brought in.
Now the prelude cannot play a DTS encoded disc either.. or maybe it can with this driver.. but what I'm trying to clarify is if this "DTS ENCODING" patch note means its just encoding an existing analog signal into a DTS one, or if will also support DTS pass-through over optical so I can listen to it on my Z5500 which it couldn't do so far.