Pixel Audio Bridge

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Most good headphones hold one Bluetooth connection at a time, so using them with your phone means unpairing them from your Mac and pairing them back afterwards.

You cannot fix that with Bluetooth. macOS has no A2DP sink, so a Mac can never appear in a phone's output list as a speaker. This moves the audio instead: over USB or your own network, out of whatever your Mac is already playing to.

What you need

Mac	macOS 14+	Apple silicon or Intel
Phone	Android 11+	USB debugging enabled
Output	Any device	Headphones, a USB DAC, or speakers
Tools	scrcpy and adb	Both free, both on Homebrew
Install	Homebrew or DMG	Signed and notarized, universal

Install

brew install --cask nicglazkov/tap/pixel-audio-bridge
brew install --cask android-platform-tools   # skip if you have Android Studio

Two commands. The first brings the app, scrcpy and the pab command; the second brings adb, which is only missing if you do not already have the Android SDK. The app checks for both on launch and tells you if either is absent, so there is nothing to get wrong.

Or download PixelAudioBridge.dmg and drag it to Applications.

Opens like any other Mac app. Apple has checked it for malware, so macOS will not warn you or block it. Universal, so it runs on Apple silicon and Intel.

Already have Android Studio? adb is at ~/Library/Android/sdk/platform-tools and the app finds it there, so skip the second command.

Your phone needs Developer options unlocked first, then either USB debugging or Wireless debugging depending on whether you are using a cable. No route skips this, because the bridge reaches your phone through adb. The getting started guide walks both, with a picture of every screen you need to find.

No cable at all? pab pair does the whole Wi-Fi pairing. It finds the phone on your network, asks only for the six digit code the phone shows, and looks up the separate port it has to connect on, so the two are never mixed up. With a cable already attached, pab enable-wireless is quicker.

brew install scrcpy
git clone https://github.com/nicglazkov/pixel-audio-bridge.git
cd pixel-audio-bridge && ./build.sh
open build/PixelAudioBridge.app

./build.sh produces a universal binary signed ad hoc, which is fine for your own machine. SIGN=developer ./build.sh signs with a Developer ID under hardened runtime, and ./release.sh runs the full notarized release pipeline.

How it reacts

When	It does
You put your headphones on	Starts by itself, within about a second
You take them off	Goes quiet and waits, then resumes when they return
You unplug the cable	Moves to Wi-Fi and widens the buffer
Your Mac's output changes	Halts instead of following it
You quit the app	Tears down every child process

Closing the window does not stop playback. The app lives in the menu bar.

Latency

Link	Buffer	Bluetooth	Total
Wired, USB	15 ms	170.7 ms	191 ms
Wireless, Wi-Fi	200 ms	170.7 ms	376 ms

The Bluetooth figure is identical in both because it happens inside the headphones. It is 89% of the wired budget and nothing on either machine changes it, so everything this software controls is the twenty milliseconds beside it.

Measured with AirPods Max. A wired output device skips that stage almost entirely. How each number was measured

Commands

pab run [--wired|--wireless] [--buffer MS] [--device UID] [--serial S]
pab pair                      # pair over Wi-Fi, no cable needed
pab stop | status | info | doctor | enable-wireless

pab doctor reports dependencies, devices, transports and config in one pass. Start there when something is wrong.

Homebrew puts pab on your PATH. If you installed from the disk image instead, it lives inside the app:

/Applications/PixelAudioBridge.app/Contents/Resources/pab doctor

Documentation

Getting started	Setting the phone up, step by step, with or without a cable
How it works	The internals, the watchdog, and how every number was measured
Troubleshooting	No sound, clicks, wireless resets, and the rest
Privacy	What is stored, and what leaves your machine. Nothing does
Security	Threat model, accepted risks, and how to report a vulnerability
Contributing	Layout, tests, and what will get pushed back on

Limitations

• Phone calls cannot be captured. Android blocks it, and there is no mic path back.
• Some apps opt out of audio capture and will be silent. Spotify does; Instagram does not.
• Video on the phone leads the audio, because the phone cannot know to compensate.
• The output watchdog takes up to about half a second, so it is not a hard guarantee.

Tests

./tests/run.sh

78 tests, none needing a phone, headphones or any audio hardware.

Built with

scrcpy does the capture and playback, and this would not exist without it. See NOTICE for attribution.

MIT licensed. See LICENSE.