One-way audio on a UCM

Fix calls where one side can't hear.

What you need	Affects
Admin access to the UCM web portal, and router access	Calls with missing audio

1. Fix NAT

External hostIn the SIP settings, set the external host or public IP and your local networks.
RTP portsOpen the RTP range on your firewall.
SIP ALGTurn off SIP ALG on your router.

Test from Wave on mobile data.

Problem	Likely cause and fix
Only remote users affected	Check remote access and port forwarding.

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