Fanvil have released a new firmware to solve the problem of a potential audio issue for the Android Phones (C400 & C600)
Recommended course of action is to upgrade the firmware for all existing devices. The firmware can accessed via the following link:
The upgrade instructions be found here Download Upgraded Guide – English .
All units that have been purchased after July 2014 should be updated.
Our Technical team will be more then glad to assist you if required. For more information please call +971 4 440 5966 Or email us firstname.lastname@example.org