1. Introduction
The SHUKE MD538 Invisible Sleep Wireless Earphones are designed for comfort and versatility, suitable for various activities including sleep, sports, and daily use. Featuring Bluetooth 5.3, IPX5 waterproofing, and a compact, ergonomic design, these earbuds offer clear audio and convenient controls.
2. Package Contents
- Charging Bin (Charging Box) x 1
- Left and Right Headphones (Earbuds) x 2
- Data Line (Charging Cable) x 1
- Product Specification (Instruction Manual) x 1
The image displays the SHUKE MD538 earbuds and their charging case, highlighting their compact design.
3. Specifications
| Feature | Specification |
|---|---|
| Brand Name | SHUKE |
| Model | MD538 |
| Material | Plastic (ABS+PC) |
| Style | In-ear |
| Communication | Wireless (Bluetooth) |
| Bluetooth Version | 5.3 |
| Wireless Range | <10m (barrier free) |
| Battery Capacity (Earbud) | 30mAh |
| Battery Capacity (Charging Case) | 300mAh |
| Play Time (Earbuds) | About 6 hours |
| Total Usage Time (with charging case) | Up to 24 hours |
| Standby Time (Earbuds) | About 90 hours |
| Total Standby Time (with charging case) | Up to 480 hours |
| Talk Time (with charging case) | About 48 hours |
| Charging Time (Earbud) | About 1-2 hours |
| Charging Time (Charging Case) | About 90 minutes |
| Charging Interface | Type-C (Micro quick charging) |
| Charging Voltage | DC 5V |
| Waterproof Rating | IPX5 |
| With Microphone | Yes |
| Voice Assistant Built-in | Yes (Apple Siri Support) |
| Noise-Cancellation | No (Features CNC noise reduction for calls) |
| Driver Diameter | 13mm |
| Frequency Response Range | 20 - 20000Hz |
| Sensitivity | 92dB |
| Impedance Range | up to 32 Ω |
| Resistance | 32Ω |
| Total Harmonic Distortion | 1% |
| Max Output | 1mW |
| Dimensions (Charging Case) | Width: 40mm, Depth: 75mm, Height: 25mm |
| Weight (Single Headset) | About 3.2g |
| Weight (Total Package) | 66g |
| Colors Available | Black, White, Khaki |
This diagram illustrates the product dimensions and key technical parameters.
4. Setup
4.1 Charging the Earbuds and Charging Case
Before first use, ensure the earbuds and charging case are fully charged.
- Place the earbuds into the charging case.
- Connect the provided Type-C charging cable to the charging port on the case and a suitable power source (DC 5V).
- The LED display on the charging case will indicate the charging status. Earbuds will automatically turn off when charging and show a white light for 1 second when fully charged.
- A full charge for the earbuds takes approximately 1-2 hours. The charging case takes about 90 minutes.
The charging case features an LED power display to show battery levels.
4.2 Binaural Pairing Connection
Follow these steps for initial pairing with your device:
- **Automatic Startup & Mutual Configuration**: Pick up both earbuds from the charging case. They will automatically power on and attempt to configure with each other. Once successful, the white and green lights of the main earbud will flash alternately, and the LED lights of the auxiliary earbud will turn off. If mutual configuration doesn't happen automatically, double-click either earbud to initiate it.
- **Device Search**: Open the Bluetooth device list on your smartphone, tablet, or computer.
- **Connect**: Search for "md528/538" in the list and click to connect. The LED light on the earbud will turn off once connected.
**Note**: If the connection fails, place the earbuds back into the charging case, close the lid, and repeat the steps above. After the first successful connection, the earbuds will automatically reconnect to the last paired device upon restart (if the device's Bluetooth is enabled).
This image shows the earbuds connected to a mobile phone, indicating successful pairing.
4.3 Wearing the Earbuds
The MD538 earbuds feature an ergonomic design for a comfortable and secure fit, even during sleep or sports activities. Their ultra-thin profile (approx. 10.6mm) ensures they do not protrude, making them ideal for side sleepers.
The image highlights the ergonomic design, showing how the earbuds fit comfortably in the ear, even when lying on your side.
This image illustrates the secure fit of the earbuds during physical activity, preventing them from falling out.
5. Operating Instructions
5.1 Power On/Off
- **Power On**:
- Pick up the earbuds from the charging case: Automatic boot, green light for 1 second.
- When earbuds are off: Press and hold the function key for 1 second. Voice prompt "Power on" with green light for 1 second.
- **Power Off**:
- Place earbuds back into the charging case and close the lid: Earbuds automatically turn off, white light for 1 second.
- When earbuds are on: Long press the function key for 3 seconds. Earbuds turn off, voice prompt "Off" with white light for 1 second.
5.2 Earbud Controls
The earbuds feature intelligent button controls for various functions:
| Function | Action |
|---|---|
| Play/Pause Music | Click L/R earbud once |
| Next Song | Right ear (R) click three times |
| Previous Song | Left ear (L) click three times |
| Volume Up | Right ear (R) click twice |
| Volume Down | Left ear (L) click twice |
| Answer/End Call | Click L/R earbud once |
| Reject Call | Long press any earbud for 1.5 seconds |
| Voice Assistant | Long press any earbud for 1.5 seconds (in connected state) |
This diagram visually represents the touch control functions for music playback and call management.
5.3 Restore Factory Settings
To restore the earbuds to their factory default settings:
- When the earbud is powered off, press and hold the function key for 8 seconds. You will hear a voice prompt "Shuts down", and the white light will be on for 1 second, indicating that factory settings have been restored.
5.4 Switch between English and Chinese
To change the voice prompt language:
- When the earbuds are powered on but not connected to any device, quickly press the function key 5 times to switch between English and Chinese.
6. Key Features
- **Invisible & Comfortable Design**: At only 10.6mm thick and weighing about 3.2g per earbud, they are designed to be worn without feeling, even when lying on your side.
- **Bluetooth 5.3**: Provides stable connection, improved endurance, and high transmission rate with reduced power consumption.
- **HD Call Quality**: Built-in dual directional microphones with CNC noise reduction technology ensure clear, face-to-face communication.
- **IPX5 Waterproof**: Resistant to sweat and splashes, making them suitable for sports and outdoor activities.
- **HiFi Stereo Sound**: Powerful unit configuration and 360° surround acoustic design for immersive audio experience.
- **Low Latency**: Smart new generation Bluetooth 5.3 chip ensures near-zero delay, synchronizing sound and picture for gaming and video.
- **Smart LED Power Display**: The charging case features an LED display to show the battery level of the case and individual earbuds.
This image compares the MD538's size and weight to a regular headphone and a coin, emphasizing its compact nature.
The image shows the ergonomic design, ensuring a comfortable and secure fit that is invisible and non-protruding.
This image explains the CNC noise reduction and dual microphone technology for clear high-definition calls.
The image illustrates the 360-degree surround sound effect, promising an immersive music experience.
This image shows the earbuds being used during exercise, highlighting their IPX5 waterproof and sweatproof capabilities.
The image displays the earbuds' compatibility with Android, Apple, and Windows devices.
This image provides a cutaway view of the 13mm dynamic horn, emphasizing its role in delivering HiFi sound quality.
The image demonstrates the earbuds' ability to connect to multiple mobile phones simultaneously, thanks to their intelligent dual processing chip.
This video demonstrates the ergonomic design for comfortable wear, intelligent button control, HiFi stereo sound quality, HD call with microphone, and 6 hours of play time, suitable for daily needs.
7. Troubleshooting
- **Earbuds not pairing/connecting**:
- Ensure both earbuds are picked up from the charging case to initiate mutual configuration.
- If mutual configuration fails, double-click either earbud.
- Verify "md528/538" is selected in your device's Bluetooth settings.
- If connection still fails, place earbuds back in the charging case, close the lid, and retry the pairing process.
- Ensure the earbuds are within 10m of your device.
- **Synchronization issues (one earbud not working)**:
- Try placing both earbuds back in the charging case and then taking them out again to force re-sync.
- If issues persist, perform a factory reset (see section 5.3).
- **Earbuds automatically shut down**:
- If earbuds are out of range from the connected device for more than 3 minutes, they will automatically shut down. Reconnect by bringing them closer to the device or restarting them.
- Ensure earbuds are charged. Low battery can cause unexpected shutdowns.
- **Low power reminder**:
- The earbuds provide a voice reminder when the battery is low. Charge them promptly.
8. User Tips
- **For Sleep**: The invisible and ergonomic design makes these earbuds comfortable for side sleepers. Ensure they are properly seated in your ear to avoid discomfort.
- **For Sports**: The secure fit and IPX5 waterproof rating make them suitable for workouts. They are designed to stay in place even during active movements.
- **Battery Life**: While earbuds offer about 6 hours of play time, the charging case extends this significantly. Keep the case charged for extended use throughout the day.
- **Call Quality**: Utilize the dual microphones with CNC noise reduction for clearer calls, especially in noisy environments.
9. Warranty and Support
This product comes with a warranty certificate. Please keep this card properly for any warranty claims or support inquiries. The warranty card includes details regarding undesirable phenomena and inspector information.
For further assistance, please refer to the contact information provided on your product packaging or the official SHUKE website.
**Regulatory Compliance**: This device contains license-exempt transmitter(s)/receiver(s) that comply with Innovation, Science and Economic Development Canada’s license-exempt RSS(s). Operation is subject to two conditions: (1) This device may not cause interference. (2) This device must accept any interference, including interference that may cause undesired operation of the device. Any changes or modifications not expressly approved by the party responsible for compliance could void the user's authority to operate the equipment.
