> ## Documentation Index
> Fetch the complete documentation index at: https://rockboxzig.mintlify.site/llms.txt
> Use this file to discover all available pages before exploring further.

# AirPlay

> RAOP streaming to one or many AirPlay receivers — Apple TV, HomePod, Airport Express, shairport-sync.

Rockbox includes a pure-Rust RAOP (AirPlay 1) implementation. ALAC frames go
out over RTP/UDP; RTSP handles session setup. RTCP NTP sync packets are sent
roughly every 44 frames so receivers stay in lockstep.

## Single receiver

```toml theme={"theme":{"light":"catppuccin-latte","dark":"min-dark"}}
music_dir    = "/path/to/Music"
audio_output = "airplay"
airplay_host = "192.168.1.50"   # IP of the AirPlay receiver
airplay_port = 5000             # optional, default 5000
```

## Multi-room

Fan-out to N receivers simultaneously:

```toml theme={"theme":{"light":"catppuccin-latte","dark":"min-dark"}}
music_dir    = "/path/to/Music"
audio_output = "airplay"

[[airplay_receivers]]
host = "192.168.1.50"   # living room
port = 5000             # optional, default 5000

[[airplay_receivers]]
host = "192.168.1.51"   # bedroom
# port defaults to 5000

[[airplay_receivers]]
host = "192.168.1.52"   # kitchen
```

All receivers share the same `initial_rtptime`, so RTP-level synchronisation
is within one frame (\~8 ms) across the LAN.

## Compatible receivers

* Apple TV (any generation supporting AirPlay 1)
* HomePod / HomePod mini
* AirPort Express
* [shairport-sync](https://github.com/mikebrady/shairport-sync) — software
  AirPlay receiver for Linux, macOS, FreeBSD, OpenWrt
* Most third-party AirPlay-1 speakers

AirPlay 2 is not implemented.

## Auto-discovery

Discovered receivers appear in the web UI device picker — click to connect
without editing the config. The mDNS service type is `_raop._tcp.local.`.

## Debugging

```sh theme={"theme":{"light":"catppuccin-latte","dark":"min-dark"}}
RUST_LOG=rockbox_airplay=debug rockboxd
```

Common log lines:

```
DEBUG  rockbox_airplay::rtsp  ANNOUNCE → 192.168.1.50:5000
DEBUG  rockbox_airplay::rtsp  SETUP  → control=53000 timing=53001 server=53002
DEBUG  rockbox_airplay::rtsp  RECORD → 200 OK
DEBUG  rockbox_airplay::rtp   sent 352 frames seq=12345
```

## Limitations

* **No password / pairing.** AirPlay 1 receivers that require a PIN are not
  supported.
* **No volume sync.** Volume changes apply only at the rockboxd side; the
  receiver's hardware volume is not adjusted.
* **No AirPlay 2.** The pairing/encryption stack required for AirPlay 2 is
  not implemented.

## Architecture

The RAOP stack lives in `crates/airplay/`:

| File      | Responsibility                                               |
| --------- | ------------------------------------------------------------ |
| `alac.rs` | ALAC escape/verbatim encoder — 352 stereo S16LE → 1411 bytes |
| `rtp.rs`  | RTP/UDP packet sender + RTCP NTP sync                        |
| `rtsp.rs` | Synchronous RTSP client: ANNOUNCE → SETUP → RECORD           |

The C-side sink is `firmware/target/hosted/pcm-airplay.c`.