When your Sonos Ace headphones flash that white (or blue) pairing light without actually connecting, it's stuck in Bluetooth advertising mode looking for a device to pair with. The fix is figuring out what's blocking the handshake, whether it's your phone, the Sonos app, or the headphones themselves.
Quickest thing to try first: unlock your phone and bring the headphones within a few feet. The Sonos Ace starts talking to your phone over Bluetooth LE when it's in pairing mode, and if your phone is locked, asleep, or Bluetooth is off, the connection never completes. Wake the phone, swipe to unlock, and you should see the Sonos Ace show up in the Bluetooth list or the Sonos app should prompt you to finish setup.
Make Sure Bluetooth Is On and Working
Open your phone's Bluetooth settings. Confirm the toggle is on. If you see other Bluetooth devices successfully connected nearby, your phone's Bluetooth radio is fine. If the list is empty or Bluetooth won't turn on, restart your phone and try again.
For iPhones, a force restart (Volume Up, Volume Down, hold Side button until Apple logo) often clears a stuck Bluetooth stack. For Android, just a standard power cycle works.
Force the Sonos Ace Out of Pairing Mode
Sometimes the headphones get stuck advertising and need to be kicked back into a fresh state. Do a quick reset of the pairing mode by turning off Bluetooth on your phone completely, then turning it back on. If the Sonos Ace was previously paired, they might try to reconnect silently instead of showing the setup card. Another trick: press and hold the Power/Bluetooth button on the right earcup for about 5 seconds until the light changes. That puts them back into pairing mode manually.
Forget the Headphones From Your Phone's Bluetooth List
If the Sonos Ace are already saved in your phone's Bluetooth paired list, even if they show as "Not Connected," that old record can block a fresh pairing operation. Go to Settings > Bluetooth, tap the (i) icon next to "Sonos Ace," then tap Forget This Device. Confirm the removal. Now put the headphones back into pairing mode (hold Power/Bluetooth until the light flashes) and they should appear as a new device ready to pair.
Reset the Sonos Ace With the USB-C Cable
If the flashing continues and no phone will pair, it's time for a full reset. Grab the USB-C cable that came with the headphones. Press and hold the Power/Bluetooth button while plugging the cable into the headphones. Keep holding the button for about 10-15 seconds until the status light changes color (typically turning solid before starting the pairing sequence again). This is the official Sonos reset method for clearing all stored connections.
The reset wipes any previous pairing state, so the headphones start fresh. After the reset, they'll automatically re-enter pairing mode and should appear on your phone without further fuss.
Check the Sonos App for Proper Setup
The Sonos app has had some notable issues since its 2024 redesign, and that can interfere with headphone pairing and management. If the app is not logged into your Sonos account, or it's on an older version, it might not recognize the Ace at all. Make sure you're running the latest version of the Sonos app from your app store. If you're on iOS 16 (which runs in unsupported mode), consider updating to iOS 17 or later for full headphone configuration. On Android, Android 10 or higher is required.
If the app is up to date, try logging out and back into your Sonos account. Then go to the headphone settings within the app to verify the Ace is listed. Sometimes just opening the app while the headphones are nearby triggers the pairing flow that the phone Bluetooth menu misses.
Try Pairing to a Different Phone or Device
Bring the Sonos Ace near a different phone or tablet that's fully up to date. If they pair and connect successfully there, the problem is specific to your original phone, not the headphones. Once paired on any device, the headphones will work with that device only (they don't sync across iCloud or Google accounts like AirPods do). But it's a great way to isolate the fault.
If they won't pair to any device at all, even after a reset, the hardware may need service. Contact Sonos support for a warranty evaluation.
Pair Over USB-C as a Fallback
If Bluetooth pairing keeps failing but you need to use the headphones right now, you can connect via the included USB-C cable. This requires firmware version 1.2 or later on the headphones. Plug the USB-C cable from the headphones into your phone, computer, or even a console with USB-C audio support. The Sonos Ace will switch into USB-C audio mode automatically. No Bluetooth pairing needed.
You'll get lossless audio this way, but you lose wireless freedom. Once the USB-C connection is established, you can troubleshoot the Bluetooth issue later without pressure.
