Do you mean an RTSP audio only stream separate from the video+audio feed you might ingest to an NVR, or combined audio/video RTSP stream? Most manufacturers of security cameras with ordinary RTSP stream functions support provide both video and audio together. 'Frigate' for instance will auto detect audio stream on a reolink camera and it "just works" in the latest versions of Frigate.
Do you mean an RTSP audio only stream separate from the video+audio feed you might ingest to an NVR, or combined audio/video RTSP stream? Most manufacturers of security cameras with ordinary RTSP stream functions support provide both video and audio together. 'Frigate' for instance will auto detect audio stream on a reolink camera and it "just works" in the latest versions of Frigate.