We are excited to introduce two major quality improvement efforts in this release!

First, we've added support for Opus RED. This brings a major step up to audio quality over lossy networks. Even with 50% packet loss, audio still comes out clear and free of robotic artifacts.

The other major feature is the ability to automatically switch to TCP or TURN/TLS when UDP connection is failing. Certain routers/firewalls would initially let through UDP packets, but then either rate limit or block them from continuing. We can detect these scenarios and switch to TCP for that participant. To enable this, set rtc.allow_tcp_fallback: true in config.

Added

• Support for NACK with audio tracks #829
• Allow binding HTTP server to specific address, binds to localhost in dev mode #831
• Packet stats from TC (#832)
• Automatic connectivity fallback to TCP & TURN (#872 #873 #874 #901 #950)
• Support for client-side ping/pong messages (#871)
• Support for setCodecPreferences for clients that don't implement it (#916)
• Opus/RED support: redundant audio transmission is enabled by default (#938 #940)

Fixed

• Fixed timing issue in DownTrack.Bind/Close (#833)
• Fixed TCPMux potentially blocking operations (#840)
• Fixed ICE restart while still in ICE gathering (#895)
• Fixed Websocket connection hanging if node isn't available to accept connection (#923)
• Fixed ICE restart/resume in single node mode (#930)
• Fixed client disconnected in certain conditions after ICE restart (#932)

Changed

• Move to synchronously handle subscriber dynacast status (#834)
• Retransmit DD extension in case packets were missed (#837)
• Clean up stats workers (#836)
• Use TimedVersion for subscription permission updates (#839)
• Cleaned up logging (#843 #865 #910 #921)
• track_published event now includes the participant's ID and identity (#846)
• Improve synchronization of track publishing/unpublish path (#857)
• Don't re-use transceiver when pending negotiation (#862)
• Dynacast and media loss proxy refactor (#894 #902)
• PCTransport refactor (#907 #944)
• Improve accuracy of connection quality score (#912 #913)
• Docker image now builds with Go v1.19