Optical cable
- Sound Output
- Optical / External Speaker
- Digital Audio Format
- PCM or Stereo
English
Interactive User Guide · Duet Aura / BTHT-6129R
Clear TV sound, without turning up the room.
Connect the transmitter by HDMI ARC, Optical, or AUX, then listen together through the two included Auracast headphones—each at its own volume.
The headphones join the transmitter's Auracast broadcast—there is no Bluetooth pairing step for normal TV use.
HDMI ARC · Optical · AUXAuracast · up to 35 hoursStart setup
How do you want to connect?
Choose the option that works best for you.
★ We recommend Duet Aura for the best experience.
How the recommended setup works
The transmitter broadcasts your TV sound.
TVYour TVHDMI ARC, Optical, or AUX output
TXDuet Aura transmitterReceives and broadcasts TV sound
HPDuet Aura headphonesJoins the Auracast broadcast
For normal TV use, do not pair by Bluetooth. A solid orange headphone LED means it has joined the transmitter.
Got it — Start setupRecommended kit setup
Four steps. One clear result.
Follow each step in order. We show what to do, what to look for, and how to fix it.
Step 1
Power the transmitter.
Place it near the TV. Keep the audio cable loose, not stretched.
Connect power
- Connect USB-C to the transmitter.
- Connect USB-A to a 5 V, 500 mA–2 A power source.
✓
Expected: the transmitter turns on. The audio-signal light may blink until the TV sends sound.
No light? Reconnect both cable ends. Then try another USB power source.
Step 2
Choose one TV audio output.
Look at the labels on the back or side of the TV, then choose the matching path.
Using a soundbar? Complete headphone setup first. Optical and AUX pass-through are covered later; HDMI ARC soundbars cannot share the ARC port directly.
Which TV output do you have?
Tap a connection to reveal its cable, switch position, and next setting.
Connect with Optical
- Remove the protective caps from both cable ends.
- Connect TV OPTICAL / DIGITAL AUDIO OUT to transmitter OPT IN.
- Set the transmitter Input Selector to OPT.
Next: set the TV sound output to Optical/External Speaker and Digital Audio Format to PCM.
Connect with HDMI ARC
- Use the TV port specifically labeled HDMI ARC or eARC.
- Connect that port to the transmitter HDMI ARC input.
- Set the transmitter Input Selector to HDMI ARC.
Next: select HDMI ARC/Receiver as the TV sound output, turn eARC off, and set Digital Audio Format to PCM.
Connect with AUX / 3.5 mm
- Connect TV HEADPHONES / AUDIO OUT to transmitter AUX IN.
- Set the transmitter Input Selector to AUX.
- Set TV sound output to Headphones and raise TV volume to a normal level.
Next: play a program with speech; PCM is normally not required for analog AUX.
Step 3
Set the TV audio output.
Use your TV remote. Then match the settings to your cable.
Use your TV remote controlThese settings are changed on the TV—not on the Duet Aura transmitter.
Choose the card that matches your cable
HDMI cable
- Sound Output
- HDMI ARC / Receiver
- eARC
- Off
- Digital Audio Format
- PCM or Stereo
3.5 mm cable
- Sound Output
- Headphones
- TV volume
- Raise to a normal level
No PCM setting needed.
Optical / HDMI ARC:Choose PCM. Dolby, DTS, Bitstream, or Auto may cause silence.
✓
Test it: play a TV program with speaking voices.
Find PCM settings for your TV brand
Step 4
Turn on both headphones.
Keep them near the transmitter.
✓
Success: the LED is solid orange. TV sound plays.
Connect both headphones
- Slide both power switches to ON.
- Wait for solid orange on each headphone.
- Put them on. Adjust each volume separately.
Red + blue flashing? Double-press ⏯, then hold it for 3 seconds. Wait for solid orange.
No sound after resuming playback? Turn the transmitter OFF, then ON again.
TV Bluetooth setup
Connect the headphones directly to a Bluetooth TV.
This bypasses the Duet Aura transmitter and may have more delay.
Turn off the transmitter
Start Bluetooth pairing
Hold the power switch at Pair with Phone for 3 seconds until red and blue flash.
Select Aria Aura
Open the TV Bluetooth audio list and select Aria Aura.
Confirm solid blue
Solid blue means the Bluetooth connection is ready.
Too much lip-sync delay?
Quick fixes
Match what you see.
Each fix states the action, expected result, and next step.
⌁Headphones won't join the transmitter
- Confirm the transmitter is on and playing TV audio.
- Keep the headphones close to the transmitter and at least 2 m from Wi-Fi routers or microwaves.
- Double-press ⏯ if the LED is red + blue, then hold ⏯ for 3 seconds until it flashes orange.
- Wait for solid orange.
Expected: solid orange and TV sound. If it still fails, hold + and − together for 5 seconds to reset the headphones, then search again.
🔇Joined, but no TV sound
- Check the cable: use a TV audio OUT port and match the transmitter selector to HDMI ARC, OPT, or AUX.
- Check the transmitter: a solid Audio Signal light means usable TV audio is arriving. If it blinks, correct the cable or TV settings first.
- Check the TV: for Optical/HDMI ARC choose the matching Sound Output and set Digital Audio Format to PCM; for HDMI ARC also turn eARC off.
- Check volume: raise the TV volume for AUX, then raise the headphone volume and try Voice Clear 1 or 2.
- Restart: turn the transmitter OFF, then ON.
Expected: the Audio Signal light is solid and spoken dialogue plays. Still silent? Reopen Step 2 and follow the matching connection path from the beginning.
ARCHDMI ARC has no sound
- Use the TV port labeled HDMI ARC/eARC—not a standard HDMI input.
- Select HDMI ARC/Receiver as TV Sound Output.
- Turn eARC off and set Digital Audio Format to PCM.
- Set the transmitter Input Selector to HDMI ARC, then restart the TV and transmitter.
A soundbar already using the ARC port must be disconnected or rerouted; Duet Aura soundbar pass-through is Optical/AUX only.
⚡No light on transmitter
- Reconnect USB-C at both ends.
- Try a known-working 5 V USB adapter.
- Slide the transmitter switch to OFF, then ON.
If there is still no light, submit a support ticket with a photo of the power connection.
🔋Headphones will not charge
- Confirm the dock has power.
- Align the charging contacts and look for solid red.
- Try USB-C charging directly.
- Allow about 2.5 hours.
Make dialogue louder
Adjust volume in this order.
1. TV and transmitter
- Using AUX? Raise the TV/source volume first.
- Need more volume? Switch Volume Boost to ON (+6 dB).
2. Headphones
- Set volume: raise it slowly.
- Dialogue unclear? Try Voice Clear 1, then Voice Clear 2.
Daily use
Charge both headphones.
Use the powered dock or a USB-C cable.
Power & charging
About 2.5 hours for a full charge.
- Use the powered dock or USB-C with a 5 V, 1–2.4 A source.
- On the dock, align the charging contacts.
- Solid red means charging; the LED turns off when full.
Not charging? Reseat the headphones or USB-C cable and verify the power source.
Battery reference
Up to 35 hours of playtime. Actual time varies with volume, connection, and use.
Daily use
Use a soundbar and headphones together.
Match the input and output cable.
Private listening
Private Mode is coming soon.
Private Mode uses an encrypted, password-protected Auracast broadcast.
What to expect
The feature is not available yet. Once released, it will be added to the headphones through a DFU firmware update.
Until then
Use the open Duet Aura broadcast for normal TV listening. The headphone app is only needed for password-protected broadcasts.
Auracast hearing aids
Use with hearing aids.
Works with compatible Auracast-enabled hearing aids.
Check the Mode light
It should be white.
Not white? Hold the transmitter Mode button for 3 seconds.
Join the broadcast
Use your hearing aids or their app to join the Duet Aura Auracast broadcast.
Expected: the Mode light is white and TV audio plays through your hearing aids.
In the box
Everything included.
2 headphones + transmitter charging dockUSB-C power cable
Optical cable
AUX cableHDMI cable is not included. Use a standard HDMI cable only when connecting through HDMI ARC.
Reference
Connections, lights, and official help.
Quick reference
- TV inputs
- HDMI ARC, Optical, or AUX
- Solid orange
- Headphones joined the Auracast broadcast
- Flashing orange
- Searching for an Auracast broadcast
- Solid blue
- Headphones connected by Bluetooth
- Red + blue
- Bluetooth pairing mode
- Charge time
- About 2.5 hours
- Playtime
- Up to 35 hours
Official resources
FIRMWARE UPDATE
Coming Soon.
Firmware update instructions are not available yet. No action is needed now.
STILL NEED HELP?
Get the right help for Duet Aura.
Choose Duet Aura / BTHT-6129R and include the TV model, connection type, LED pattern, and a clear photo of the TV and transmitter ports.
RECOMMENDEDSubmit a Duet Aura support ticketAdd photos or screenshots so the team can see the exact wiring and TV settings.Start support request →
DON'T WANT TO SUBMIT A TICKET?
Talk to a real support agent.
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