INTERVAL Swim Headphones for Apple Watch

With Bluetooth & MP3




How to & troubleshooting


There are 4 key steps to get your Apple watch set up and running with your favorite music, audio-books or podcasts. 

1. Sync Apple watch with iPhone to Download music, podcasts and audio-books directly to your watch via a compatible app to enable offline playback.

  • Download the content you want to listen to from your choice of compatible apps to your watch.*The Interval is not required for this first step. When adding content to your watch you will need your iPhone. WIFI is recommended to speed up download times to your watch. Please note, many apps require a subscription to enable offline playback.
  • Use any app that is compatible with your smartwatch and allows offline playback. Below are links with instructions on how to download or add content from some of the most popular apps directly to your Apple watch.
  • Apple Music
  • Spotify
  • Pandora Plus
  • Audible

2. Pair your Apple watch via Bluetooth to the Interval.

3. Clip the Apple watch or attach a smart watch to the Interval.

  • The watch has to come off your wrist.

4. On your Apple watch, open an app and playback your downloaded content.

Helpful video:
Watch on Youtube


1. Enable Bluetooth in the settings of your Apple watch:

  • Power on your watch, navigate to Apple Watch>Settings>Bluetooth.
  • Ensure Bluetooth is on.

2. Power On the Interval:

  • Make sure the Bluetooth on your phone is off so it does not interfere.
  • Press and hold the center “O” button for 2 seconds on the Interval until the light rapidly blinks red and blue. A rapidly blinking Red and Blue light indicates pairing mode.
  • When you see the H2O Interval appear on your watch tap the text to complete the connection

3. Pairing Your Device:

  • For first-time pairing, wait for the, ”H2O INTERVAL” name to appear on the Bluetooth screen of your smartwatch.
  • Once it appears, tap on the, ”H2O Interval” text to complete the Bluetooth pairing process.
  • When a connection is made the Interval LED will turn blue and slowly blink.

4. Reconnecting Previously Paired Devices:

  • If your H2O Audio device has been paired with the source device before, it should automatically reconnect.

5. Start Streaming:

  • Make sure you have set up your Apple watch for offline playback. See previous section, “Apple Watch Set Up”. if you have not completed this step.
  • On your Apple watch, open an app and playback your downloaded content.

6. Disconnecting:

  • To disconnect, you can either turn off your H2O Audio device, disconnect from the Bluetooth settings on your source device, or simply stop the Bluetooth connection directly from your source device.

If you're encountering issues with Bluetooth pairing between your Interval and smartwatch, try the following steps:

 1. Kill', all the open and active apps on the watch. 

2. Go to Watch Settings > Bluetooth > find the H2O Interval. Tap the Info icon and then select the FORGET THE DEVICE. Now you have unpaired the Interval.  

3. Restart Both Devices:

  • Power off both your smartwatch and the Interval.
  • After a brief moment, power them back on to reset the Bluetooth connections.

4. Attempt to Re-Pair:

  • Retry the pairing process by putting both devices in pairing mode according to their respective instructions.

5. Need Further Assistance?

  • If the problem persists, our support team is available to help. Please reach out via chat, email, or phone for personalized assistance.



  • When swimming the drag of the water or tugging of the speaker wires may cause the speakers to dislodge. If the speakers are moving or falling out, wrap the speaker wire around your goggle strap and then place the speakers in your ears. This will reduce the drag and help keep them securely in place.
  • If you have a swim cap, pull the cap over the ears and tuck the earphones under the cap for a secure fit.
  • Experiment with the different sizes and styles of ear plugs to find the best fit. You may need two different sizes for either the left or right ear as each ear canal can vary.
  • We also offer custom molded earplugs. They provide a custom fit and deliver exceptional sound quality. H2OAUDIO.COM


  • For the best sound experience orient the speakers to be in front of the ear. Try to find a location on the goggles that provides the best sound. Bone conduction works by the vibration of the speaker that is conducted to the inner ear.
  • Tip: For the best sound experience in the water, we recommend using the included solid earplugs. This will block ambient sounds and splashing water.


We use our patented waterproofing technology that sometimes requires the speakers to be equalized due to pressure. Think of the speakers as an empty plastic water bottle - and if you take that in an airplane it will deform due to ambient pressure which is different from the pressure inside the bottle. We need to get the bottle to release and pop it back to normal form.

If there is a faint or muffled sound this can be resolved via the  troubleshooting steps below. If there is buzzing crackling or is completely silent this cannot be fixed. In this case, please contact us directly:


If you are experiencing sound quality issues - there are a few possible scenarios:

  • There is water trapped between the speaker and the earplug. Solution: tap the speakers and try to get the drop of water out. Also gently blowing into the speaker might help. Once the water dries up - it should sound normal. To avoid this during swimming, try different size earplugs and find one that keeps the best seal/fit.
  • The speaker is not completely equalized. Solution: Play loud/full volume music through the speakers and let the music run for a while. This will slowly help equalize the speakers. To expedite, you can gently suck and blow air into the speaker which will reset the membrane.
  • If you remove the blue ear tips and tap the speaker on a firm surface you can release the membrane.
  • Soak the affected speaker in very warm water to break down any residue or build up - repeat steps 1-4.
  • Please test the headphones on a different device to determine if the issue is the source device or the headphones.


  • If either side of your Interval bone conduction speakers is not producing sound please reach out directly via email:

Download the free My Swim Tracker app to log all your swim workouts. My Swim Tracker will keep track of your PRs, distances, and provide audio lap counting. It will coach you and encourage you to reach your goals. Complete your Apple Activity Rings and enjoy lap swimming.

MY SWIM TRACKER APP - Troubleshooting

1. Lap Detection Issues: The My Swim Tracker App is still in beta testing and we are collecting more data to make it more accurate and will make app updates soon. Here are tips to help the lap detection:

  • 1. Power off the watch and iPhone and restart them.  
  • 2. Make sure you start the app at the side of the pool (not in the locker room). 
  • 3. After you press start - wait until you hear that it is OK to start swimming. The watch is calibrating before the start. 
  • 4. Make sure that the Apple Watch is clipped to the Interval with the buttons pointing to the right. If the watch is upside down, it will not work well.

2. Not Connecting to Apple Health

  • The Apple Health can be activated from the Phone app, but you will also need to verify this in the watch app. Open the watch app and see.
  • If you missed this when you first installed the app you will need to delete the app from your phone and your watch.
  • After you delete the app from both your phone and watch power off both devices, restart and then re-install the app on both the phone and watch.
  • Once the watch app is installed, open the MySwimTracker watch app. On the 1st opening - it will ask if you want to allow the linking  - select the option there and confirm.+

Need Help? We’re Here for You! If you have any questions or need support, our customer service team is eager to assist. We're committed to ensuring your H2O Audio experience is both seamless and enjoyable.

Live Chat:

1-Year Warranty

All H2O Audio products are covered by a 1-year warranty from the date of purchase, protecting against manufacturing defects under normal use. For any issues covered by our warranty, please contact our customer support for assistance and resolution.


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