SIP Trunk One-Way Audio or RTP Troubleshooting
This article aims to help you understand and resolve SIP Trunk one-way audio or RTP issues with your Bigfoot Voice service. These problems can manifest as calls connecting or answering, but one side cannot hear the other, both sides have silence, or audio is intermittent.
Why It Matters
Reliable communication is essential for any business. One-way audio or RTP issues can disrupt your business operations, leading to missed opportunities, lost sales, and customer dissatisfaction.
How It Works
SIP trunk calls use Real-time Transport Protocol (RTP) to transmit audio data. When one-way audio occurs, it's often due to issues with RTP, network address translation (NAT), firewalls, or codec negotiation.
What You Should Know
- Call Examples: Provide detailed call examples with direction, caller ID, called number, timestamp, and which side could hear audio.
- Affected Direction: Determine whether the issue affects inbound, outbound, all calls, specific destinations, or only remote/mobile callers.
- Network Configuration: Share your PBX/SBC public IP, LAN/NAT topology, RTP port range, SIP ALG/firewall inspection status, and media anchoring settings.
- Codec Negotiation: Provide details about offered/answered codecs and any transcoding if available.
- Packet Evidence: Check whether packets are reaching the PBX/SBC and whether RTP source/destination IPs match the expected public addresses.
Common Questions or Issues
Common questions or issues include understanding the role of RTP, NAT, firewalls, and codecs in SIP trunk calls. Other questions may revolve around the impact of network path changes or the use of SIP ALG.
How Bigfoot Voice Handles This
At Bigfoot Voice, we escalate issues like these with SIP/RTP call examples, media direction, network path, and recent firewall/NAT/PBX changes. Our goal is to quickly identify and resolve the root cause of the problem.
If you're experiencing one-way audio or RTP issues, please follow the steps outlined above to provide us with the necessary information. We're here to help you maintain clear and reliable communication.
Remember, this article is a guide to help you understand the issue and provide the necessary information for our support team. For internal agent procedures, diagnostic checklists, or escalation steps, please refer to our internal resources.