Copying audio only works after opening original stream once

[felipecrs]

go2rtc version: 1.6.0

config:

streams:
  camera_01:
    - rtsp://192.168.1.20/Streaming/Channels/101
  # Used to discard audio track, workaround for:
  # https://github.com/AlexxIT/go2rtc/issues/198
  camera_03_internal:
    - rtsp://192.168.1.20/Streaming/Channels/301
  camera_03:
    - rtsp://127.0.0.1:8554/camera_03_internal?video
    - rtsp://127.0.0.1:8554/camera_01?audio

Basically, I want to copy the audio from camera_01 to camera_03, discarding the existing audio from camera_03 (#198).

However, when I first try to stream camera_03, there is no audio. But if I stream camera_01, and unmute the audio, now audio starts working with camera_03 too.

chrome_B2KCwFxstz.mp4

[AlexxIT]

Is problem relevant on 1.6.2?

[felipecrs]

Testing, one sec.

[felipecrs]

Yes, the exact same problem happens with 1.6.2.

[felipecrs]

Just to update, this still happens on 1.7.0, my config is now:

  # Copy audio from camera_03 to camera_01:
  camera_01:
    - rtsp://admin:pass@192.168.1.20/Streaming/Channels/101#media=video
    - rtsp://127.0.0.1:8554/camera_03?audio
  camera_03:
    - rtsp://admin:pass@192.168.1.20/Streaming/Channels/301

[felipecrs]

It seems that when streaming camera_01, it does not automatically open the stream to camera_03.

[felipecrs]

One workaround I found was to add the camera_03 from go2rtc to Home Assistant, and enable the preload option, so that go2rtc keeps a stream to it always open.

[felipecrs]

I did not test explicitly, but with things like #media=video I think this now works as expected.