One-way audio issues and their troubleshooting

Troubleshooting one-way audio issues

One-way audio can occur for various reasons (vendors, equipment, incorrect UA configuration, firewall settings, etc.).

Troubleshooting these issues depends on the call flows and multiple factors, and we will cover several fixes here. If the issue continues, please find H323-Conf-ID and report the issue to Support. 

1.1. Caller can't hear Called Party.

On-net call: check if another destination works (for example, call UM - *98) to understand the source of the issue. If the issue continues when the other destination is called, make sure nothing is blocking incoming media packets (a general recommendation is to allow all UDP ports > 1024 for VoIP devices). Check if SIP ALG is enabled in the caller's router settings. We recommend SIP ALG be disabled.

Off-net call (DID provider -> Sagecom): place an on-net call to this DID, to clarify if the DID provider is a root of the issue. If yes, please report the issue to your DID provider.

Off-net call (Sagecom -> termination vendor): place a call using another vendor. 

1.2. Called Party can't hear Caller.

On-net call: make sure nothing is blocking incoming media packets at the callee's side.

Off-net call (DID provider -> Sagecom): if an on-net call to that DID does not indicate the issue, please report the issue to the DID provider.

Off-net call (Sagecom-> termination vendor): place a call using another vendor. Ask Support to check RTP proxy logs (if used), to be sure media was indeed sent by the caller.

Forcing RTP proxy for the affected account(s) may help in some cases, or may even be required (when mobile softphone(s) is used), therefore this can be considered as a workaround. However, ideally media should flow directly using the shortest path.