Justin Napolitano

A minimal shell-based setup to enable AirPlay and Spotify Connect on ThinkPad laptops using ALSA only, avoiding PulseAudio or PipeWire. Includes a hum silencer script to eliminate idle audio noise.

Features

AirPlay receiver support via Shairport-Sync
Spotify Connect support via librespot
ALSA-only audio handling with system-wide dmix for mixing multiple audio streams
Hum silencer script to play a silent tone preventing idle hum on Realtek ALC257 codec

Tech Stack

Shell scripting (Bash)
ALSA (Advanced Linux Sound Architecture)
Shairport-Sync (AirPlay receiver)
librespot (Spotify Connect client)

Getting Started

Prerequisites

ThinkPad laptop with Realtek ALC257 codec (or similar ALSA-compatible hardware)
ALSA installed and configured
Shairport-Sync installed
librespot installed

Installation

Configure ALSA for system-wide dmix by creating or editing /etc/asound.conf with the provided dmix configuration (see below).
Place stop-hum.sh somewhere accessible (e.g., your home directory or /usr/local/bin/).
Make sure the silent tone file exists at ~/Music/tones/silence.wav or update the script path accordingly.
Set up Shairport-Sync and librespot to use the ALSA dmix device as output.

Running

To silence the idle hum after AirPlay disconnects, run the script:

./stop-hum.sh

This script waits 2 seconds, then plays a silent tone to keep ALSA inputs stable.

Project Structure

index.md       # Documentation and setup notes
stop-hum.sh    # Shell script to play silent tone on AirPlay disconnect

ALSA dmix Configuration Example

# Mix multiple playback clients on Analog (hw:0,0)
pcm.dmixed_analog {
  type dmix
  ipc_key 1024
  ipc_key_add_uid false
  ipc_perm 0666
  slave {
    pcm "hw:0,0"
    rate 44100
    format S16_LE
    channels 2
    period_time 0
    period_size 1024
    buffer_size 8192
  }
}

pcm.!default {
  type plug
  slave.pcm "dmixed_analog"
}

ctl.!default {
  type hw
  card 0
}

Adjust hw:0,0 if your sound card differs.

Future Work / Roadmap

Automate hum silencer trigger on AirPlay disconnect events
Expand support for other hardware codecs
Integrate librespot and Shairport-Sync service management
Provide packaged installer or systemd service files
Add detailed troubleshooting and configuration guides