Thanks for the response.
The basis for my question is what I read on the DSD forum page here:
Digital Speech Decoder (software package) - The RadioReference Wiki
The following formats are currently under investigation or development:
P25 Phase 2 - standard not finalized yet, vocoder is supported by mbelib
OpenSky - four slot format vocoder may be supported by mbelib. Will not be supportable if it is determined that voice encryption is standard
D-STAR - Voice frames recognized, vocoder not supported by mbelib. May be possible to pass voice bits to DVDongle.
Other formats will only be considered if high quality samples of the signals are made available for download by the developers. Samples must be from a discriminator tap, .wav format, 48000Hz, 16 bits per sample, mono.