Avantree BTTC-218
Avantree Relay User Manual
Model: BTTC-218
Wireless Audio Transmitter
Introduction to Avantree Relay
The Avantree Relay is a versatile Bluetooth 5.3 adapter designed to bring wireless audio to your travels and daily activities. With Qualcomm aptX Adaptive support, it ensures high-quality sound with minimal latency. Connect up to two pairs of Bluetooth headphones or AirPods simultaneously to share your audio experience. Its compact design and long battery life make it an essential companion for flights, gym sessions, and more.

Image: Avantree Relay Bluetooth Adapter with included dual 3.5mm adapter.
What's in the Box
Your Avantree Relay package includes everything you need to get started:
- 1 x Relay Transmitter
- 1 x Dual 3.5mm Male to 3.5mm Female Adapter
- 1 x USB-C Charging Cable (1.5ft / 0.5m)
- 1 x Traveling Pouch

Image: All items included in the Avantree Relay product box.
Product Overview
Familiarize yourself with the Avantree Relay's features and controls:
- 3.5mm AUX Connector: For connecting to audio sources like airplane entertainment systems, TVs, or gym equipment.
- ON/OFF Switch: Located on the side for easy power control.
- Volume Adjustment Buttons: Control audio output volume directly from the device.
- Multifunctional Button (MFB): Used for pairing, reconnecting, and checking battery level.
- Connection Indicators: LEDs (1 and 2) to show status of connected headphones.
- Battery Status Indicator: Four LEDs indicating remaining battery life.
- USB-C Charging Port: For recharging the device.

Image: Detailed view of the Avantree Relay showing its various buttons and indicators.
Setup Guide
Setting up your Avantree Relay is simple. For an interactive guide, scan the QR code on the product or refer to the user manual PDF.

Scan for Interactive User Guide

Interactive Setup Guide on Phone
Initial Pairing
- Turn off phone's Bluetooth: To avoid interference, ensure Bluetooth is disabled on your smartphone or other previously paired devices.
- Power on Relay: Slide the ON/OFF switch to the 'ON' position. For first-time use, the Relay will automatically enter pairing mode (LED flashes blue and red alternately).
- Put Headphones/AirPods into Pairing Mode: Place your Bluetooth headphones or AirPods into their pairing mode. For AirPods, place both in their case, open the lid, and press & hold the button on the back of the case until the LED indicator flashes white.
- Connect: Keep the Relay and your headphones/AirPods close together. They will automatically connect within a few seconds. Once connected, the Relay's connection indicator LED will turn solid blue.

Image: Ensure your phone's Bluetooth is off.

Image: Put your AirPods into pairing mode.
Using the Dual 3.5mm Adapter
For airplane entertainment systems with two audio jacks, use the included dual 3.5mm adapter. Simply plug the Relay's 3.5mm connector into the adapter, then plug the adapter into the airplane's audio jacks.

Image: Avantree Relay connected to the dual 3.5mm adapter.
Operating Instructions
Connecting to an Audio Source
Plug the Relay's 3.5mm AUX connector (or the dual adapter if needed) into your desired audio source. This could be an airplane's in-flight entertainment system, a TV, or gym equipment.

Image: Avantree Relay connected to an airplane seat's audio jack.
Connecting Two Headphones
The Relay allows you to connect two pairs of Bluetooth headphones simultaneously for shared listening.
- First, successfully connect your first pair of headphones as described in the Setup Guide.
- Once the first pair is connected, press & hold the Relay's Multifunctional Button (MFB) until the connection indicator LED flashes blue and red alternately. This puts the Relay back into pairing mode for the second device.
- Put your second pair of Bluetooth headphones into pairing mode.
- Keep the Relay and the second pair of headphones close together. They will automatically connect. Both connection indicator LEDs on the Relay will turn solid blue once both headphones are connected.

Image: Two people enjoying shared audio using the Avantree Relay.
Battery Life & Charging
The Avantree Relay offers up to 20 hours of playtime, sufficient for most long flights. The battery status indicator LEDs show the remaining charge. To charge, connect the provided USB-C cable to the Relay's charging port and a USB power source.
- Double-click the MFB to check the battery level.
- It's best to initiate charging when the Relay is at 25% battery level or below.
- The Relay can be used while charging.
Maintenance
To ensure the longevity and optimal performance of your Avantree Relay, follow these simple maintenance tips:
- Keep the device clean by wiping it with a soft, dry cloth.
- Avoid exposing the device to extreme temperatures, humidity, or direct sunlight.
- Store the Relay in its traveling pouch when not in use to protect it from dust and scratches.
- Do not attempt to disassemble or modify the device, as this will void the warranty.
Troubleshooting
Encountering issues? Here are solutions to common problems:
Headphones Not Pairing/Connecting
- Ensure Pairing Mode: Double-check that both the Relay and your headphones are correctly in pairing mode (Relay: LED flashes blue & red; Headphones: refer to their user manual).
- Disable Other Bluetooth Devices: Turn off Bluetooth on your smartphone, laptop, or any other device that your headphones might automatically connect to. This prevents interference during pairing.
- Clear Pairing History: On the Relay, press & hold both the '+' and '-' volume buttons for 6 seconds to clear its pairing history. Then, try pairing again.
No Sound or Low Volume
- Check Volume Levels: Ensure the volume on both the Relay (using the +/- buttons) and your connected headphones is turned up. Also, check the volume on the audio source (e.g., airplane screen, TV).
- Verify Connection: Confirm that the Relay's connection indicator LED is solid blue, indicating a successful connection to your headphones.
- Re-plug Relay: Disconnect and re-connect the Relay's 3.5mm AUX connector to the audio source.
- Restart Devices: Turn off both the Relay and your headphones, then turn them back on and attempt to reconnect.
Reconnecting Issues
Once paired, your headphones should automatically reconnect to the Relay when both are turned on. If not:
- Manual Reconnection: Press the Relay's Multifunctional Button (MFB) once to manually initiate the reconnection process.
- Power Cycle: Turn off both the Relay and your headphones, then turn them back on.
Helpful Videos
Video: Interactive User Guide - Avantree Relay Bluetooth Adapter. This video provides a comprehensive interactive guide for setting up and using your Avantree Relay.
Video: Tips & Tricks - Avantree Relay Bluetooth Adapter for Plane. Learn useful tips and tricks for optimizing your experience with the Avantree Relay, especially during flights.
Specifications
| Feature | Detail |
|---|---|
| Model Number | BTTC-218 |
| Bluetooth Version | 5.3 |
| Audio Codecs | Qualcomm aptX Adaptive, aptX Low Latency |
| Playtime | Up to 20 hours |
| Input | 3.5mm AUX |
| Dimensions | 6.46 x 5.75 x 0.67 inches |
| Item Weight | 4.5 ounces |
| Color | Black |
Warranty & Support
Avantree products are backed by a 24-month warranty from the date of purchase, ensuring peace of mind.
For further assistance, detailed FAQs, video tutorials, or to download the full user manual, please visit the official Avantree support website or contact customer service:
- Official User Manual (PDF): Download Here
- Avantree Support: Visit www.avantree.com/support
- Seller: AvantreeDirect USA
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