SONAR Underwater Headphones with MP3 & BT

With PLAYLIST+, Bluetooth & MP3



How to & troubleshooting


Required Equipment:

  1. H2O Audio Device (SONAR)
  2. Supplied USB Data and Charging Cable
  3. Computer or Laptop

Ensure that the audio files you intend to download are in one of the supported formats and are free from any digital rights management (DRM) protection. Supported Audio Formats, (MP3, M4A, WMA, FLAC. APE).

1. Connect Your SONAR:

  • Use the USB cable provided with your SONAR to connect it to your computer or laptop.
  • Ensure a secure connection to enable file transfer.

2. Device Recognition:

  • Upon successful connection, your computer should automatically detect the device and display it as an external drive.
  • If the device does not appear automatically, manually check your computer's file manager (for PC users) or Finder (for Mac users).

3. Troubleshooting Connection Issues:

  • If the device is not recognized, verify the connection and try reconnecting. Ensure the cable is properly plugged into both the device and the computer.

4. Locate Music Files:

  • Find the music files you wish to transfer on your computer. These could be in your iTunes library or any other folder where you store audio files.

5. Transfer Music Files:

  • Select the desired audio files and either drag and drop them into your device's folder or copy and paste them directly.
  • Wait for the transfer to complete before disconnecting the device. Ensure all files are fully copied to avoid data loss.

6. Managing Device Content:

  • To remove files from your device, navigate to the device folder, select the unwanted files, and either right-click to delete or drag them to the trash.

7. Safely Disconnecting the Device:

  • Before disconnecting the USB cable, ensure you safely eject the device from your computer to prevent data corruption.

8. Listening to Music:

  • Power on your H2O Audio device, switch to memory mode, and enjoy your music underwater without interruptions.

For optimal performance, regularly update your device firmware and check for new supported formats or features. Enjoy your underwater audio experience with H2O Audio!


If you're experiencing difficulties connecting your SONAR to your computer or laptop, follow these troubleshooting steps to resolve the issue:

1. Restart Your Computer:

  • Occasionally, USB ports can become unresponsive. Restarting your computer can reset these ports and potentially fix the connection issue.

2. Try a Different USB Port:

  • Not all USB ports operate at the same efficiency. If one port doesn't recognize your device, try another.

3. Check the Device Indicator:

  • Upon a successful connection, your SONAR should show a lit green LED light indicating it's properly connected.

4. Listen for Confirmation:

  • A successful connection is often accompanied by an audio chime or prompt from your computer, signaling device recognition.

5. Accessing Your Device

  • Your SONAR should appear as an external drive. On Windows PCs, check your File Manager; on Macs, use Finder.

6. Need Further Assistance?

  • If you're still encountering issues, our support team is ready to assist via chat, email, or phone.

It's important to understand the distinction between protected and purchased music when downloading files to your H2O Audio device:

  • Accepted File Formats: Your device supports MP3, M4A, WMA, and APE formats. Ensure your music files are in one of these formats and are DRM-free.
  • Subscription-based Services: Music from platforms like Apple Music, Spotify, Amazon Music, iHeartRadio, and Pandora is typically protected with DRM and cannot be directly downloaded to your device, as these services offer access to music rather than ownership.

Direct Downloads Only: Your device accepts files that are directly downloaded and unprotected. This ensures compatibility and uninterrupted playback.


If you're unable to transfer purchased music from iTunes, consider the following:

  • Cloud-based Music: Verify if your music is stored in iCloud rather than on your device. Look for a cloud symbol with a downward arrow next to the track in iTunes.
  • Downloading from iCloud: Click the cloud symbol to download the music file to your computer's hard drive. This step is necessary before transferring music to your H2O Audio device.
  • Transferring Music: Once downloaded, you can drag and drop or copy and paste the music files into your device's memory.
  • Further Assistance: If problems persist, our customer support is available to help via chat, email, or phone.

For any additional questions or support, don't hesitate to contact our customer service. We're here to ensure your H2O Audio experience is seamless and enjoyable.

  1. It is possible to use the Bluetooth function of the Sonar. You will need a waterproof smart watch (Apple Watch) and the Sonar Clip for Apple watch. You must attach the watch to the clip and then to the Sonar. This will enable you to access app based music premium subscriptions for offline playback via a Bluetooth connection.
  2. For swimming we also recommend using built-in memory that you can use to playback your downloaded music files uninterrupted while submerged.  You will need to add the content you want to playback to the watch.
  3. Bluetooth does have limitations when lap Swimming. Bluetooth does not penetrate water well (laws of physics), the range is only a few inches underwater. so you will need to keep the Bluetooth source (Apple Watch) Close to the receiver of the Sonar set.
  • Attach your Apple Watch to your goggles.
  • Secure clip with patent pending attachment system
  • Flexible silicon locking bands will secure the Apple Watch in place under the most rigorous activities.
  • Compatible with ALL Apple Watch models - including ULTRA!
  • Listen to music from your Apple Watch via Bluetooth - underwater. (MUST be clipped on your swim goggles or within few inches of the player)


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.

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.


Pair your H2O Audio device to a smartphone or smartwatch for direct live streaming of audio content with these simple steps:

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 Your H2O Audio Device:

  • Turn on your H2O Audio device and listen carefully to the audio prompts.
  • By default, the device will start in either Bluetooth (BT) or Memory Mode.

3. Switch to Bluetooth Mode:

  • If your device starts in Memory Mode, switch to Bluetooth Mode.
  • Consult your H2O Audio device's user guide for instructions on toggling to BT mode.

4. Pairing Your Device:

  • For first-time pairing, wait for your H2O Audio Device's name to appear on the Bluetooth screen of your source device.
  • Once it appears, tap on the device name to complete the Bluetooth pairing process.

5. Reconnecting Previously Paired Devices:

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

6. Start Streaming:

  • Play audio content from your preferred app on the source device to start streaming through your H2O Audio device.

7. 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 H2O Audio device and your phone or smartwatch, try the following steps:

1. Restart Both Devices:

  • Power off both your source device (smartphone or smartwatch) and the H2O Audio device.
  • After a brief moment, power them back on to reset the Bluetooth connections.

2. Attempt to Re-Pair:

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

3. 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.

Simultaneously press and hold the Play/Pause & M button for 15 seconds to reset the device.

*Please note: Performing a reset will not erase any downloaded audio from the memory device.


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:

Call:            858.771.4410

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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