(1) All NVR WiFi sets support two-way audio function (e.g. NVS001, NVS002, NVS004, NVS009)
(2) NVR connected via wired network do not support two-way audio function, but only support monitoring function (e.g. NVS003, NVS005, NVS006, NVS007)
Note: XVR does not support two-way audio function, only supports monitoring function (e.g.NVS008)