In version 1.0 of the software, the decoder was the XAudio decoder.

In version 2.0 of the software, the decoder is (if I recall correctly) the ARM decoder.

In theory, you could replace the decoder with anything you wanted to code up and compile. The problem is that the actual PLAYER software is integrated with the decoder and is not open-source.

So. If you want to replace the decoder, you must also write your own full replacement for the player software, too. No one has done this for the empeg car player yet.