Avantree BTTC-218 Support Center Relay

- Relay Transmitter
- Dual 3.5mm Male to 3.5mm Female Adapter
- USB C Charging Cable (1.5ft / 0.5m)
- Traveling Pouch
Product Overview
- ON / OFF switch
- Volume adjustment button
- Multifunctional button (MFB)
- Connection indicator
- Battery status indicator
Button Functions
| No. | Button | Functions |
|---|---|---|
| 1 | ON/OFF | Switch to turn the Relay on/off. Press once or hold to adjust volume. Press & hold both for 6 seconds to clear pairing history. Press & hold for 2 seconds to enter pairing mode. |
| 2 | Volume adjustment | Press once or hold to adjust volume. |
| 3 | Multifunctional Button (MFB) | Press once to manually initiate reconnection to last-paired device. Double click to show battery level. |
LED Indicators
| No. | Indicator | Status |
|---|---|---|
| 1 | Alternate red & blue Pairing flashes | |
| 2 | Solid blue | Connected |
| 3 | Blue flashes every second | Reconnecting to last-used device |
| 4 | Blue flashes every 5 seconds | Standby |
| Any of the 4 LED indicators | Charging | |
| All the 4 LED indicators off | Fully charged | |
| Solid white for 1 second (after power on) | ||
| Battery status | ||
Charging the TransmitterDouble click the MFB to check the battery level. It’s best to initiate charging when the Relay is at 25% battery level or below.
- Plug the provided USB C charging cable into the charging port.
- Connect the other end to a 5V/500mA-2A rated USB adapter (your phone charger or similar should work) or PC USB port.
- A flashing white light on the transmitter indicates that charging is in progress; the four lights will turn solid white then off to indicate a full charge.
Connecting to an Audio SourcePlug the Relay into an in-flight entertainment system (use the adapter if necessary) or any other audio source with an AUX 3.5mm audio connector.
Connecting to Your Headphones
- Slide the Relay’s ON/OFF switch to the ON position. For first time use, the Relay will enter PAIRING mode automatically. For subsequent use, put your Relay into PAIRING mode by pressing & holding the MFB until the LED flashes blue and red alternately.
- Put your Bluetooth headphones into PAIRING mode.
- Keep the Relay & your device close together and wait for 5-10s until they connect. Once connected, the indicator will turn solid blue.
NOTE: Most cases where your device & the transmitter fail to connect happen because the device is not properly placed into PAIRING mode. Double check that your device is successfully in PAIRING mode (typically indicated by an LED indicator’s alternate red & blue flashes). For more details, please refer to your device’s online user manual.
Box Contents
Product Overview
| No. | Button | Functions |
| 1 | ON | Switch to turn the Relay on / off |
|
2 |
| Press once or hold to adjust volume |
| Press & hold both for 6 seconds to clear pairing history | ||
|
3 |
Multifunctional Button (MFB) | Press & hold for 2 seconds to enter pairing mode |
| Press once to manually initiate reconnection to last-paired device | ||
| Double click to show battery level |
LED Indicators
| No. | Indicator | Status |
|
A | Alternate red & blue flashes | Pairing |
| Solid blue | Connected | |
| Blue flashes every second | Reconnecting to last-used device | |
| Blue flashes every 5 seconds | Standby | |
| Solid blue & red simultaneously for 3 seconds | Clearing pairing history | |
|
B | Any of the 4 LED indicators flashing | Charging |
| All the 4 LED indicators off | Fully charged | |
| Solid white for 1 second (after power on) | Battery status |
Charging the Transmitter
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.
- Plug the provided USB C charging cable into the charging port, then connect the other end to a 5V/500mA-2A rated USB adapter (your phone charger or similar should work) or PC USB port.
- A flashing white light on the transmitter indicates that charging is in progress; the four lights will turn solid white then off to indicate a full charge.
Connecting to an Audio Source
Plug the Relay into an in-flight entertainment system (use the adapter if necessary) or any other audio source with an AUX 3.5mm audio connector.
Connecting to Your Headphones
- STEP 1
Slide the Relay’ ONs
OFF switch to the “ON” position. For first time use, the Relay will enter PAIRING mode automatically. For subsequent use, put your Relay into PAIRING mode by pressing & holding the MFB until the LED flashes blue and red alternately.
- STEP 2
Put your Bluetooth headphones into PAIRING mode. - STEP 3
Keep the Relay & your device close together and wait for 5-10s until they connect. Once connected, the indicator will turn solid blue.
NOTE: Most cases where your device & the transmitter fail to connect happen because the device is not properly placed into PAIRING mode. Double check that your device is successfully in PAIRING mode (typically indicated by an LED indicator’s alternate red & blue flashes). For more details, please refer to your device’s online user manual.
Adding a Second Pair of Headphones
You can connect and simultaneously listen through two pairs of headphones if desired.
- STEP 1
Once your first device is successfully connected, put your Relay into PAIRING mode once again by pressing & holding the MFB until the LED
flashes blue and red alternately. - STEP 2
Put your second pair of Bluetooth headphones into PAIRING mode. Please refer to your headphones’ user manual for more details if necessary. - STEP 3
Keep the Relay & your second device close together and wait for 5-10s until they connect.
Once connected, both
indicators will turn solid blue.
NOTE: The dual headphones support function works with most headphones but not all. Certain true wireless earbuds in particular do not work well with Bluetooth transmitters’ dual headphones mode. If you’re not getting audio while dual linked, try turning the
affected headphones off and then on again. In some cases, dual pairing with Airpods may trigger their audio MUTE function. If this happens, put them back in their charging case (with the lid open) for 2 seconds, then take them out again to return them to normal. This may help to solve the problem.
Reconnecting Your Headphones
You typically do NOT need to re-pair your Bluetooth headphones with the Relay every time. Once successfully paired, they should automatically reconnect when both devices are turned on (this may take a few seconds).
If your device does not automatically reconnect after 5-10 seconds, you can manually initiate reconnection by pressing the Relay’s MFB once and waiting for 5-10 seconds. If this still doesn’t work, try initiating reconnection on your audio device as well (typically done by pressing the main Bluetooth PLAY button on your headphones once). If they still don’t connect, you may need to re-pair your device.
NOTE: If you paired your headphones with a different Bluetooth device, turn Bluetooth OFF on said device(s). Airpods in particular will always prioritize Apple devices for automatic pairing, so you’ll need to turn your iPhone’s Bluetooth OFF when pairing your Airpods with the Relay.
Specifications
| Bluetooth version | v5.3 |
| Supported profiles | A2DP; AVRCP |
| Audio codecs | aptX adaptive; aptX LowLatency, aptX, SBC |
| Input voltage / current | DC5.0V / 500Ma-2A |
| Operating range | Up to 33ft / 10m |
| Product dimensions | 125mmx24mmx12mm |
| Net weight | 15g |
FAQ
Below are some of the most common questions people have during setup.
- My Relay’s at max volume; why is the sound still so quiet?
Try adjusting the volume on both the Relay, your headphones, and / or the audio source. You should be able to reach sufficient volume levels by adjusting all three. - Can I use this while it’s charging?
Yes, you can use it while it’s charging. - Does this work on a regular TV?
As long as your TV has an AUX or RCA audio output jack, the Relay will work with it. Please note that you’ll need an AUX 3.5mm to RCA adapter (not included) in order to transmit audio via your TV’s RCA ports. - Why am I getting audio delay?
Both the sender (i.e. the Relay) and the receiver (i.e. your Bluetooth headphones) must support either aptX Low Latency or aptX Adaptive in order to eliminate audio latency. You can check your device’s specs to ensure it supports either of these audio codecs. Please note that most true wireless earbuds do not currently support aptX Low Latency or aptX Adaptive audio codecs. - Why aren’t my headphones connecting?
- Why aren’t I getting sound from my headphones?
For answers to questions like these and for a full FAQ list, you can visit avantree.com/support/relay, or you can contact us directly for additional assistance.
Contact Us
- Support Tickets avantree.com/submit-a-ticket
- Support Email [email protected]
- USA / CA +1800 232 2078 (9am-6pm PST, Mon-Fri )
- UK +44 20 8068 2023 (9am-6pm, GMT, Mon-Sat)
- DE +49 32221097297 (11am-9pm, CET, Mon-Sat )
- FR + 33 176340312 (11am-9pm, CET, Mon-Sat )
- IT +39 06 9480 3330 (9am-6pm, CET, Mon-Sat )
- ES + 34 931786261 (9am-6pm, CET, Mon-Sat )
- AU + 61 2 8310 9897 (11am-7pm, AEST, Mon-Fri)
- FAQ avantree.com/support/relay
- Product Registration avantree.com/product-registration
Manufacturer: Avantronics Limited
Address: Luohu District, Shenzhen 518000 China
US Importer: Avantree Corporation San Jose, California 95119 USA
UK Importer: Avantree Limited
Watford, WD180 0HQ UK
Servicer in Europe:
Gizmex GmbH,
Sternstr.67,40479 Dusseldorf, Germany
Tel:01–4083348648 [email protected]
Model No:BTTC-218 Dispose of the packaging and this product in accordance with the latest provisions. Z-PKQG-BTTC-218-V1
























