<Global Settings>
Network → NAT Settings
<sip_stun_bindtime_ determine>VALIDVALUE</sip_stun_bindtime_ determine>
If STUN is enabled and sip_stun_bindtime_guard is defined, setting this to 1 forces the base to automatically determine the duration of NAT bindings in the system. In this case, sip_stun_bindtime_guard defines the initial test duration.
off / on
on