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AirPlay to a Raspberry Pi: what quality actually arrives

Guide 6 · 4 min read

Short answer: on Linux, AirPlay is received by shairport-sync. In classic AirPlay, it always gets CD quality: ALAC, 16 bits, 44.1 kHz, lossless, whatever the music's own resolution. In AirPlay 2, an iPhone, iPad or Mac sends most apps' music as lossy AAC at 48 kHz, according to shairport-sync's author; only a HomePod mini or an Apple TV 4K sends lossless, at 24 bits and 48 kHz. Nothing above 48 kHz arrives. Raspberry Pi OS and Debian 13 ship the classic version.

Checked on 2026-10-22 against shairport-sync's documentation and source code — version 5.6.1, and 4.3.7 as Debian 13 ships it —, Debian's packages and Apple's pages, which do not say what AirPlay carries; measured on two test boxes.

What arrives

AirPlay Sent by What arrives
Classic any Apple device or app ALAC, 16 bits, 44.1 kHz: lossless, CD quality
AirPlay 2, real time Spotify's free tier, or a Mac's whole sound ALAC, 16 bits, 44.1 kHz
AirPlay 2, buffered most apps on an iPhone, iPad or Mac AAC at 48 kHz, 44.1 on older systems: lossy
AirPlay 2, lossless a HomePod mini or an Apple TV 4K playing the music itself ALAC, 24 bits, 48 kHz
  • Apple does not publish this. The table comes from shairport-sync's documentation and from its author, Mike Brady, who reads what reaches his receiver (2026). Of higher resolutions he writes: "We don't know how to decipher higher resolutions"; 96 and 192 kHz are not received.
  • The Apple device chooses, among the formats the receiver says it takes, and can switch from lossy to lossless during a stream.
  • When a HomePod mini or an Apple TV plays to several speakers, all of them receive what the weakest takes.

On Raspberry Pi OS or Debian

sudo apt install shairport-sync
shairport-sync -V

The second command says what you have. Debian 13's package, as installed on Raspberry Pi OS, answers 4.3.7-libdaemon-OpenSSL-Avahi-ALSA-…: classic AirPlay. A version built for AirPlay 2 carries -AirPlay2 in that line.

Its settings are in /etc/shairport-sync.conf. The name Apple devices show, and the DAC it plays on, with your card's number from aplay -l:

general = {
    name = "Living room";
};
alsa = {
    output_device = "hw:0,0";
};

Then sudo systemctl restart shairport-sync.

  • Classic AirPlay shows in the AirPlay list of iPhones, iPads and Macs, but cannot join other speakers for several rooms at once, and does not appear in the Home app.
  • AirPlay 2 needs shairport-sync built with --with-airplay-2, and its companion NQPTP, which Debian 13 does not have and which must have ports 319 and 320 to itself: shairport-sync's build guide gives the steps.

What shairport-sync does to the sound

  • It keeps time. To stay in step with the sender, it now and then adds or removes a frame. Its author: this "inevitably must degrade the audio fidelity, even if it is very hard to hear"; the All Sync PPM figure of its statistics can stay at 0.0 for long periods on a well sorted system.
  • Its volume. By default, shairport-sync lowers the level itself, and adds dither when it does. With mixer_control_name in its alsa section, the DAC's own volume does it instead. With ignore_volume_control = "yes", the level stays at full: in its author's words, "a clean, unmodified stream of audio".
  • The rate sent to the DAC. Version 4.3.7 picks the lowest rate the DAC takes, and the greatest bit depth; version 5 matches what arrives when it can. Measured on my test box, with shairport-sync 5.5 in classic AirPlay and its volume in software (2026-10-22): the output received 44,100 Hz in 32-bit words, S32_LE in its hw_params (see How to check bit-perfect playback).

When it fails

  • fatal error: could not establish a service on port 5000 -- program terminating. Is another instance of Shairport Sync running on this device? — a second shairport-sync on the same box. Measured with one already running.
  • warning: The output device "hw:0,0" is busy and can't be used by Shairport Sync at present. — another player holds the DAC (see "Device or resource busy").
  • The Pi is not in the AirPlay list. The Apple device and the Pi must be on the same network, not on a guest Wi-Fi or another VLAN.

With Audiogravity

Audiogravity installs the box system's shairport-sync, names the receiver after the box, and sends it to the output you choose for it in the guided setup — another one than MPD's if you like, the box's optical output for instance.

The details are in the manual: First run → Per-service outputs.

Sources