Grandstream UCM Remote Connect (UCMRC) Strict RTP causes no audio between IP Phones

Strict RTP Grandstream UCMRC Remote Connect


There is no audio issue in the calls between IP Phones using UCMRC. However, audio works when the call is established between the Wave app and the IP Phone with the same registered extension.


The “Strict RTP” option cannot be enabled while using the remote domain address of UCMRC services.

When using the UCMRC service, the RTP packets will be forwarded through the TURN server, but the IP phone will carry its public IP address, which means the source addresses in the RTP packets are inconsistent. When this option is enabled, the RTP packets with different source addresses will be dropped, which causes this no-audio issue between the IP Phones.