Mac screen mirroring sound output: get the picture on the TV and the sound on a speaker

What happens to the sound while a Mac is mirroring

A Mac treats a screen-mirroring session as one destination for both halves of the stream. Pick a TV, an Apple TV, or a receiver app from Screen Mirroring in Control Center, and macOS hands that destination the picture and the sound together. The Sound pane in System Settings, the Sound tile in Control Center, and the Option-click list behind the menu-bar volume icon all show the same output list, with the mirroring target as the active output.

Pick a different AirPlay device from that list — a Sonos, a HomePod, any AirPlay 2 speaker — and the Mac does not add a second destination. It replaces the first one. The mirror ends, the TV drops back to its idle screen, the video keeps playing on the Mac's own display, and the audio comes out of the speaker. An Apple Community thread titled "AirPlay mirroring stops when audio output is changed" and a Sonos Community answer that switching the Mac's sound to a Sonos disables the screen and only plays sound both describe exactly this.

The route that keeps both is not on the Mac. An Apple TV 4K takes the whole mirror and re-routes the audio itself, through Settings → Video and Audio → Audio Output. An Xbox running Xbox Advanced AirPlay Receiver (Xaar) does the same job when the box under the TV is an Xbox One or Series X|S. Full disclosure: Xaar is our app.

Every Sound-output option on a Mac while mirroring, and what it does

The five answers on the search page, checked

Each of these is right about something and wrong about the thing you asked.

• "Use the Sound tile in Control Center, not the mirroring menu." The Sound tile does move the audio to the speaker. It also ends the mirror, because the speaker replaces the TV as the AirPlay destination.
• "Set the output to the Apple TV before you start mirroring." This fixes the no-sound case: pointing the output at the TV puts the audio on the TV. It does nothing for a separate speaker.
• "Buy an Apple TV 4K." Correct, and it is the receiver-side answer for an Apple household. If the box under your TV is an Xbox, Xaar does the same job without adding a second box.
• "Make a multi-output device in Audio MIDI Setup." It stacks local outputs so they play together. AirPlay 2 speakers are not on its list, and it carries no picture. More on it below.
• "It is not possible." Not possible from the Mac side. Possible on the receiving end, which is the setup this page is about.

Picture on the TV, sound on a speaker: route the audio on the Xbox

The mirroring itself is the ordinary Mac flow, covered in its own guide. The steps below pick up when the Mac's screen is already on the TV and you want the sound somewhere else. The Xbox, the Mac, and the speaker must share one local network; Ethernet on the console is fine as long as the cable goes to the same router.

1. 01

   Open Xaar's menu with Y on the controller The status line shows which device is mirroring, and the output list shows every AirPlay 2 speaker Xaar has found on the network. Discovery is automatic; nothing to pair.

2. 02

   Pick the speaker from the output list Select your Sonos, your HomePod, or any other AirPlay 2 speaker. Xaar connects with no PIN, and from that moment the mirrored audio plays on the speaker while the picture stays on the TV. The Mac still sees one destination, because there is one: the Xbox does the routing.

3. 03

   Switch on the lipsync delay It is a switch in the same menu. The speaker leg is a real AirPlay 2 sender, and AirPlay 2 schedules playback at exact timestamps with a declared latency, so Xaar knows how far the speaker will lag and holds each video frame back by that amount. The delay is known, not guessed.

4. 04

   Dial in the trim once The audio buffer row sets the speaker's total delay, 250 to 2000 ms in 50 ms steps. The lipsync trim row goes from −500 to +500 ms, 1 ms per press and 10 ms when held, and covers the fixed output lag of your particular speaker and TV. Xaar remembers the trim per output device.

5. 05

   Change the volume from whichever control is nearest The volume keys on the Mac, the volume row in Xaar's menu, the speaker's own buttons or app: all of them move the same volume, and the Mac's own volume slider follows. Xaar shows the Mac's volume on the TV.

Can a multi-output device in Audio MIDI Setup do it?

No. A multi-output device is a virtual output that copies one audio signal to several physical outputs at once. Two things keep it away from this task. AirPlay 2 speakers such as Sonos and HomePod are not available inside a multi-output device, so the destination you want is not on the list. And it is audio only: it has no say over where the picture goes, so it cannot keep alive a mirror that macOS has already decided to end.

What Xaar adds beyond moving the sound

• The controller becomes the remote. X plays and pauses, the left bumper goes to the previous track, the right bumper to the next, and the commands go straight to the player on your Mac. The speaker's own controls reach the player too: pause on the Sonos pauses the video on the TV.
• One volume on every knob. Change it on the Mac, in Xaar's menu with the D-pad in 5% steps, or on the speaker itself; every control stays in sync, including the Mac's own volume slider. Volume is remembered per speaker.
• Lip-sync control down to 1 ms, stored per output device, on top of the protocol-scheduled delay.
• Hardware video decoding on the console, H.264 up to 1080p at 60 fps, with frames shown on the Mac's own timeline for smooth playback.
• One click to switch between the TV and a speaker mid-session. Xaar remembers the last speaker and reconnects to it at launch.
• Speakers are optional. With none chosen, the sound plays on the TV together with the picture.
• Everything stays on your local network: no accounts, no analytics, no cloud, no ads.
• A one-time purchase on the Microsoft Store for Xbox One and Xbox Series X|S: no subscription, no in-app purchases.

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