MODEL INSTRUCTIONS
Nano V2 microSD kit instructions
Charge the neckloop, prepare MP3 files on a suitable card and use the wired playback buttons. Nano V2 plays local recordings; it has no microphone or phone-call connection.
Before you start
Rechargeable neckloop, wired buttons, supplied 8 GB microSD card, file reader and passive Nano receivers.
Use MP3 files in the card’s root directory. This model supports cards up to 16 GB.
1. Check your kit and selected receiver
Check the model label before following these instructions. Keep the tiny Nano receivers separate from the larger extractor magnet and the extractor bar.
- Nano V2 rechargeable neckloop with wired buttons.
- Two Nano receivers, an extractor magnet and an extractor bar.
- An 8 GB microSD card, supplied in the neckloop.
- A USB-microSD reader and a USB-to-USB-C adapter for file transfer.
The current receiver choices are Nano, Nano + Vip Pro SuperMini, Nano + Vip Pro SuperMini Beige, and Nano + Vip Pro UltraMini. A Nano + Vip Pro option adds one selected Vip Pro receiver and two 337/SR416SW cells. These cells are for that optional receiver; they do not power the Nano receivers or charge the neckloop.
2. Charge and switch on
Charge the neckloop
- Move the side switch to the printed OFF position.
- Remove the lower cover to expose the built-in USB connector.
- Connect it directly to a computer USB port or a 5 V, 1 A USB power supply.
- The red charging light is on while charging and goes out when charging is complete. Allow approximately 1–1.5 hours.
- Disconnect the USB and replace the cover before use.
Switch on
Move the side switch to the printed ON position. The green light shows the card and playback state described below. Switch to OFF after use and while charging.Operation is approximately three hours, depending on volume and use. Continuous maximum volume reduces battery life. If the kit is stored for a long period, use and recharge the battery at least once every three months.
3. LEDs and playback controls
A steady green light has different meanings at startup and during playback. Check the context before treating it as a card fault.
| When | Light | Meaning |
|---|---|---|
| Charging | Red on | Battery charging. |
| Charging | Red off | Charge complete. |
| Startup | Green blinking | Loading a track and starting playback. |
| Startup | Green steady | The card is missing or cannot be read. |
| During playback | Green steady | Playback paused. |
| During playback | Green blinking | Playing, changing a track or responding to a button. |
| Control | Action | Result |
|---|---|---|
| Wired next/previous button | One click | Next or previous track. |
| Wired next/previous button | Hold | Fast-forward or rewind. |
| + | One click | Increase volume one level. A beep marks the maximum. |
| + | Hold | Cycle ordered, shuffle and repeat modes. |
| − | One click | Decrease volume one level. The minimum is silent. |
| − | Hold | Restart the current track. |
| Play/Pause | Press | Resume a paused recording. |
The neckloop’s own next/previous buttons are disabled on this version; use the wired buttons instead. The volume buttons have resistance to reduce accidental presses. Use a deliberate press without forcing them. There are 30 volume levels: start low and use the lowest audible level.
4. Prepare the microSD recordings
Choose and fit the card
The supplied card is 8 GB. Nano V2 supports microSD cards up to 16 GB. Do not choose a larger card for this model.
- Switch the neckloop off before replacing the card.
- Push the fitted card inward and release it to remove it.
- Insert the replacement card and push until it clicks into place.
Transfer files
Choose one of these methods:
- Keep the card in the neckloop, switch the neckloop on and connect its USB to a computer for file transfer.
- Remove the card and connect it to a computer with the supplied USB-microSD reader.
- Use the USB-to-USB-C adapter with a phone that supports that reader and USB file access.
Use the correct format and order
- Save recordings as
.mp3files. - Place them in the card’s root directory, outside folders.
- Number the file names in the desired sequence, for example
1.mp3,2.mp3and3.mp3. - Test a known MP3 track first. The factory test tracks can be deleted after this check.
- If tracks remain out of order or deleted tracks still appear, back up the files and format the card as FAT32 on a computer, then copy the recordings back. Formatting erases the card.
Check that ordered playback is selected: holding + changes the playback mode. Disconnect the card from the computer after the file transfer has finished.
5. Run the tabletop audio check
- Use a quiet room and keep every small part on a table.
- Identify the two small Nano receivers and separate them if they have arrived joined together. Do not confuse them with the larger extractor magnet.
- Switch on the charged neckloop with a correctly fitted card and start a known MP3 recording.
- Place the two Nano receivers and extractor magnet together against the neckloop on the table.
- Check for faint sound or vibration outside the ear. Increase the volume gradually for the tabletop test; return to a low level before use.
If there is no response, charge the neckloop for at least an hour, check the ON switch, check that the volume is above zero, and try another MP3 file in the card’s root directory. Do not treat a successful test as proof that an in-ear position is safe.
6. Optional Vip Pro receiver
This section applies only to a Nano + Vip Pro option. A Nano-only kit does not need a 337 cell.
Fit the 337/SR416SW cell
- Unscrew the receiver cap with your fingers.
- Fit one 337/SR416SW cell with its positive (+), marked face upward.
- Refit the cap carefully so it is aligned and closes correctly.
Check the optional receiver on a table
With the neckloop on and a known track playing, place the receiver close to the neckloop on the table and check for sound. A hiss alone does not verify correct operation. If it produces loud buzzing, remove the cell, check its polarity and refit the cap without forcing it. If the problem continues, contact support; do not stretch the internal spring or insert a needle into the receiver.The cell is used whenever it is fitted. Remove it after use, including when the receiver is not producing audio.
7. Neckloop position, removal and storage
The neckloop goes around the neck. Position the wired buttons where you can operate them comfortably and keep the wires clear of movement. The powered neckloop is not washable: remove it from clothing before washing and keep it dry.The Nano removal accessories are the extractor bar and the larger extractor magnet. Keep them separate from the receivers. Do not put an extractor tool into the ear canal or use sound loss to decide that a receiver has been removed. Account for all small parts after use.For an optional Vip Pro receiver, its transparent retrieval thread is for removal. Only hold it with your fingers when it is already accessible; stop if the receiver does not come out easily. Remove its cell after it is out of the ear.
Do not insert cotton buds or tools into the ear canal, or push a receiver deeper. If removal is difficult, stop and get medical care. Seek urgent care for severe pain, bleeding or discharge; a battery in the ear needs immediate medical help. See Mayo Clinic: foreign objects in the ear and NHS: earwax build-up.
Switch the neckloop to OFF after use. Clean the removed Nano receivers, extractor magnet and extractor bar with water or isopropyl alcohol only outside the ear. Keep liquids away from the powered neckloop. Let the removed parts dry completely before storing them. Ask support about the cleaning method for an optional Vip Pro receiver; do not probe its openings with a needle.
Fix a failed check
The neckloop does not switch on. What should I check?
Switch it off and charge it through its USB connector with a 5 V, 1 A supply or computer. Allow 1–1.5 hours and check the red charging light. Then disconnect it and use the printed ON position. If it still does not start, contact CooMax support.I hear nothing or very little.
First repeat the tabletop test. Check that the card is fitted, is no larger than 16 GB, and has a known MP3 in its root directory. Check that playback is not paused and the volume is above zero. Wear the neckloop around the neck for use. For an optional Vip Pro receiver, also check the 337 cell, positive face upward, and the cap alignment. Do not push a receiver deeper to solve low volume.Only one receiver seems to work.
Confirm that you have identified the two tiny Nano receivers rather than the extractor magnet, then check the neckloop, track and volume on the table. For the optional receiver, check its cell and cap separately. If a part still does not respond, contact support rather than assuming the receiver cannot be faulty.The optional Vip Pro receiver makes a loud buzzing sound.
Remove its cell and refit it with the positive (+) face up. Align the cap carefully. Try the other supplied 337 cell if the first has been left installed. If buzzing continues, stop using it and contact support; do not pull the internal spring or probe the receiver openings.My recordings play out of order, or deleted tracks still play.
Save MP3 files in the root directory with numbered names and select ordered playback. If that does not resolve it, back up the recordings, format the card as FAT32 and copy the files back. Formatting deletes the card’s contents.The green light stays on and nothing plays.
If playback had already started, it may simply be paused: press Play/Pause. At startup, a steady green light can mean an unreadable or missing card. Check the card seating, maximum 16 GB size, MP3 format and root directory, then try a known track.The next/previous or volume buttons do not work.
Use the wired buttons for next and previous; the equivalent neckloop buttons are disabled on this version. Click rather than hold + or − when adjusting volume. Holding + changes playback mode, and holding − restarts the track. Use a deliberate press; stop and contact support if a control needs force or still does not respond.I cannot remove the receiver.
Do not insert tools, force the receiver or keep repeating unsuccessful attempts. Stop and get medical care if removal is difficult. Severe pain, bleeding or discharge needs urgent care, and a battery in the ear needs immediate medical help. CooMax support can help identify the kit’s parts, but is not a substitute for medical care.It worked earlier but has stopped.
A neckloop left on can run out of charge. Switch it off and recharge, then repeat the known-track test. Check the card and playback state too. A Vip Pro cell left in the optional receiver can be depleted even when no audio plays; fit a charged replacement of the correct type.Battery life is short.
Charge with the neckloop off until the red light goes out. Avoid continuous maximum volume and use the lowest audible level. Use and recharge the stored battery at least once every three months. Nano V2 does not use a phone’s volume controls for playback.Care and safety
Do not push a receiver deeper or put tools or cotton buds into the ear canal. If removal is difficult, stop repeated attempts and get medical help. Severe pain, bleeding or discharge needs urgent care; a battery in the ear needs immediate help.
Mayo Clinic: ear foreign-object guidance · NHS: earwax advice
Keep power parts dry and follow the model-specific storage and charging steps above. If equipment is damaged, stop using it and contact model support.
Get model-specific help
Tell us the card capacity, MP3 file location, startup light and whether a known track passed the tabletop test.
Choose another model’s instructions