I would get in touch with Humanware; as other have said V Stream is able to
play Audible formats. However, things you can try:
• Update the firmware on your device. For instructions and to download the
latest software, head to
http://support.humanware.com/en-united_kingdom/support/vr_stream_software
• To play Audible Enhanced formats on the V Stream first generation, you have
to have Stream Softpack installed on your device. You don’t need Stream
Softpack to play Audible format 4. Humanware used to sell Softpack as an
additional software for the V Stream first generation, but I don’t know what
the situation is with that these days.
Hope this helps.
Amro