What audio formats are supported by synthesizeToFile method? The examples I've read always refer to the WAV format, but I could not find a list of all supported formats. Moreover, what are the supported audio files for playback by the TTS engine (addEarcon and addSpeech methods)?
I expect all you can get is WAV: staring at one version of the code it appears that the return type is PICO_DATA_PCM_16BIT (see line 656).