# OBS Receiver Setup

Add each stream as a separate OBS Media Source.

For every source:

1. Add `Sources > + > Media Source`.
2. Uncheck `Local File`.
3. Set `Input` to the relevant SRT URL.
4. Set `Input Format` to `mpegts`.
5. Enable `Restart playback when source becomes active`.

## Default URLs

These match `config/localcast.example.json` when the receiver is listening locally:

```text
video:   srt://0.0.0.0:5100?mode=listener&latency=120000&timeout=5000000
desktop: srt://0.0.0.0:5101?mode=listener&latency=120000&timeout=5000000
voice:   srt://0.0.0.0:5102?mode=listener&latency=120000&timeout=5000000
```

If using a passphrase, append:

```text
&passphrase=YOUR_SECRET&pbkeylen=16
```

OBS should be open before the sender starts if OBS is the SRT listener. If a source gets wedged, deactivate and reactivate the Media Source before changing ports; port churn is a symptom, not a configuration strategy.

## Synchronization

The video SRT source is a timed media artifact in the Aquarium path, not just scenery in OBS. Keep the listener URL and latency aligned with `stream_spout.py`:

```powershell
.\.venv\Scripts\python.exe .\scripts\stream_spout.py `
  --remote-video-url "srt://0.0.0.0:5100?mode=listener&latency=120000&timeout=5000000" `
  --remote-video-latency-ms 250
```

The live sync heartbeat is `calibration/runs/av-sync-status.json`. `remote-video-latency-ms` is presentation delay, not merely the SRT URL's `latency` parameter. Check `remote_video.delta_ns` before trusting the composite. If that number grows, fix the configured media delay or the ingest path instead of eyeballing it in OBS like a doomed little stage magician.

## Source Layout

Recommended OBS scene:

```text
Husband PC - Video       Media Source, monitor off
Husband PC - Desktop     Media Source, audio only, monitor as needed
Husband PC - Voice       Media Source, audio only, monitor as needed
```

Mute the video source if it carries no audio. Keep audio filters on the separate audio sources.