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One-way-audio in some incoming calls from PSTN to MS Teams Client
Hi all, We have a direct routing setup in place and it is working fine for the most of the times. (2 x Cisco 4300 Series SBC with the supported SW version, SBC has a public IP assigned directly - ...
IT turned out to be a NAT issue, needed to modify firewall config. Now it is working properly.
I agree with Satish (@RealTime_M365) on this. One way audio is usually always a firewall issue resulting from media legs not being allowed. The most common case I've found is defining a media range in your SBC to be from ports X to Y, but only allowing some portion of that range through.
I've seen this on AudioCodes SBCs when doing the configuration because you define the starting port, and the number of media legs, for example 50000, and 100, which one might think would be from ports 50000-50100, but they space out the ports, and it's more likely to be 50000-51000 because of the spacing.