The Ghost Music
macOS has a notorious and deeply ingrained behavior regarding media keys and Bluetooth audio devices. If you press the “Play/Pause” button on your Mac’s keyboard, or if you connect a Bluetooth headset and tap the physical play button on the earcup, macOS attempts to figure out what you want to listen to. If no other media application (like Spotify or a YouTube tab in Safari) is currently active or has recently played audio, macOS will fall back to its default: it will automatically launch the Apple Music app in the background and often start playing the first song in your local library alphabetically. This results in users being suddenly blasted with unexpected music just because they bumped their headphones.
Blocking the Media Key Hijack
Because Apple hardcodes this behavior into the operating system without a simple settings toggle, you must use a third-party utility or a background script to intercept the media keys and stop macOS from automatically launching Apple Music.
The most reliable, non-destructive method for average users is to utilize a free, open-source background utility specifically designed for this exact problem, such as noTunes. Download the noTunes application from its official GitHub repository or via Homebrew (brew install --cask notunes). Once installed, drag it to your Applications folder and launch it. A small icon (a musical note with a slash through it) will appear in your top right Menu Bar. That is all you have to do. While noTunes is running, it silently intercepts the specific macOS command that attempts to launch the Apple Music application, completely blocking the auto-launch behavior while still allowing your play/pause buttons to control Spotify or web browsers normally.