From reading the documentation, audio files need to be:
* 16-bit little endian (not sure if signed or unsigned? ffmpeg has both s16le and u16le).
* 48 kHz sampling
IIRC Eduoard was asked once to support other formats but said no, probably because this is a relatively minor feature.
I imagine that ffmpeg can probably be used to generate such files from WAV, MP3, etc, but not quite sure of the exact ffmpeg command to make that work.
Does anyone have any experience with this? If so, please share (cannot find in the documentation).
Thanks and 73s,