Select "Advanced | Audio Decoders..." to see the list of audio decoders supported by the software.
When River Past software sees a compressed audio stream, it will try to find a decoder using this list. You can use
and
to change the priority of the decoders.
More importantly, you can add your own decoder with the
button.
The decoder must be a DirectShow component. It can be a DirectShow filter, or a DirectX Media Object (DMO).