IT

Interactive user guide

HT41866-Q Setup Guide

TV earbud setup

Connect your TV to the transmitter, then listen together through two included pairs of NB16-Q earbuds.

Use the included transmitter. Both pairs of earbuds are included and pre-paired.

Start SetupFix a problem

Requires Bluetooth headphone support.

HT41866-Q transmitter with two included pairs of NB16-Q neckband earbudsPre-pairedUp to 20 hours

Recommended kit setup

Set up with the transmitter

  1. 1Cable
  2. 2Power
  3. 3TV sound
  4. 4Listen

Step 1 of 4 · Cable

Connect your TV

Check the labels beside the ports, then choose the first match below.

TV HDMI ARC portOnly HDMI ARC / eARC?Use HAX06 Converter
TV has red / white AUDIO OUT?

Use an RCA-to-3.5 mm adapter cable (not included).

Not sure? Take a photo of your TV ports.

Contact Support →

Connect RCA audio OUT

Requires: an RCA-to-3.5 mm adapter cable, not included.
Red / white AV IN sockets will not work.

  1. TV: connect red and white RCA plugs to the matching AUDIO OUT sockets.
  2. Transmitter: connect the 3.5 mm end to AUX.
✓
Ready

The TV audio OUT connects to the transmitter AUX input.
No AUDIO OUT label? Choose another connection.
Next: power on the devices →

Connect the Optical cable

  1. Remove the clear protective caps from both cable ends.
  2. TV: plug into OPTICAL / DIGITAL AUDIO OUT.
  3. Transmitter: plug into the OPTICAL / OPT input.
    Match the plug shape and insert gently.
✓
Ready

Both square plugs are fully inserted.
Do not force the cable into the port.
Next: power on the devices →

Connect the AUX cable

  1. TV: plug into HEADPHONES / AUDIO OUT, not AV IN.
  2. Transmitter: plug into AUX.
✓
Ready

Both round plugs are fully inserted.
The TV may mute its speakers when you use its headphone jack.
Next: power on the devices →

Step 2 of 4 · Power

Power on the transmitter and earbuds

  1. Transmitter: connect USB-C power, then switch ON.
    Use TV USB or a 5 V USB adapter.
  2. Both pairs of NB16-Q earbuds: on each pair that is OFF, hold the multi-function button (MFB) for 3 seconds.
  3. Connect: keep both pairs close to the transmitter and wait 5–10 seconds.
✓
Connected: the LED on each pair and transmitter listener indicators 1 + 2 are solid blue.

Next: set the TV sound in Step 3 →
Otherwise, no sound.

No light or not connected?

No transmitter light: reseat both USB cable ends and try another USB power source. More power help →

No earbud light: charge NB16-Q, then unplug the charging cable before use.

Both on, but not connected: re-pair the earbuds and transmitter →

USB power: USB-C connects to the transmitter; USB-A connects to TV USB or a 5 V / 500 mA–2 A adapter. Keep USB power connected during use.

Connection check: listener 1 and listener 2 should both be solid blue, along with the LED on each NB16-Q. One blue listener light means only one pair is connected. Connect the missing pair →

Step 3 of 4 · TV sound

TV sound settings

Use your TV remote.

Choose your cable in Step 1 to see the matching TV settings.

Open
Settings → Sound / Audio
Choose how you want to listen

TV menus vary. See the guide below.

Set Digital Audio Format to
PCM or Stereo
Avoid Dolby, DTS, Auto or Bitstream.

These may cause silence.

AUX 3.5 mm

Set the TV audio output

Open
Settings → Sound / Audio
Set Sound Output
Headphones or Audio Out
TV output volume
Raise gradually, if adjustable.

Using RCA? Check your TV manual for the audio OUT setting.

See how to set PCM

Why PCM? PCM is an audio format the transmitter supports.

Choose your TV brand:

Samsung LG Sony TCL Roku Hisense VIZIO Philips Panasonic Sharp Insignia Other TV brand

Next: listen to your TV →

TV speakers + earbuds?See if your TV supports both →

Step 4 of 4 · Listen

Listen to your TV

After completing the TV sound settings:

  1. Play TV audio. Choose a program with speaking voices.Check: the transmitter input light is solid white.
    No white light? Check settings and cable →
  2. Put on both pairs of NB16-Q. Each listener presses + / − on their own earbuds to adjust their volume independently.
  3. Check both pairs. Confirm both listeners hear TV speech. If only one pair plays, check the silent pair →
✓
Success: listener 1 + 2 and both earbud LEDs are solid blue, and both listeners hear TV sound.
No soundCannot connect

Next time: reconnect to your TV

Turn the transmitter ON. On each NB16-Q pair that is OFF, hold MFB for 3 seconds. Keep both pairs nearby and wait 5–10 seconds.
If a pair does not reconnect, press its MFB once or its transmitter listener button (1 or 2) once. Reconnect the missing pair →

DIRECT TV BLUETOOTH

Pair directly with your TV

Requires a TV that supports Bluetooth headphone audio.
This route may have more sound delay than using the included transmitter.

For two listeners, use the included transmitter. Direct TV Bluetooth depends on how many headphones your TV supports. A TV that supports one Bluetooth headphone cannot play to both pairs this way. The steps below connect one NB16-Q pair.

  1. Turn the transmitter OFF. Turn off Bluetooth on nearby phones previously paired with NB16-Q.
  2. Put NB16-Q in pairing mode. Start with the earbuds OFF.
    Hold the multi-function button (MFB) for about 5 seconds, past power-on, until red / blue alternate and you hear “Pairing.”
  3. Open your TV’s Bluetooth audio list. Look in the TV Sound settings.
  4. Select the earbuds. Choose Avantree NB16T-Q or NB16T, as displayed.
    Confirm the TV’s connection prompt.
  5. Play TV audio. Press earbud + / − to adjust volume.
Where is the Bluetooth list on Samsung TVs?

On supported Samsung TVs: Home → Settings → Sound → Sound Output → Bluetooth Speaker List.

Done: the earbud LED is solid blue and you hear TV sound.

If not: verify the TV supports Bluetooth audio, return the earbuds to red / blue pairing mode and retry.
If your TV has no Bluetooth audio list, use the transmitter setup →

No sound

Reconnect next time

Turn on NB16-Q.
If needed, press MFB once or select the saved earbuds in your TV Bluetooth list.
Re-pair if you used another device.

Fix a problem

Connected, but no TV sound

Possible cause: HT41866-Q is connected wirelessly, but the TV output, audio format, cable or volume is wrong.

For transmitter setup, a solid white input indicator confirms a valid TV audio signal.
Solid blue confirms Bluetooth only.

  1. For transmitter setup, check both ends of the TV cable and use AUDIO OUT.
    For direct Bluetooth, keep the transmitter OFF and select the earbuds as the TV sound output.
  2. For Optical, set TV output to Optical and format to PCM / Stereo.
    Check PCM on a connected streaming box too.
  3. Play speech and raise the NB16-Q volume with +.
    For AUX, raise TV output volume if available.
  4. If the earbud LED is not solid blue:
    Using the transmitter? Re-pair the kit →
    Using TV Bluetooth? Repeat direct TV pairing →

Expected: the earbud LED stays solid blue and TV speech plays through the earbuds.

Still silent? Contact Support with the cable type and both LED states.

Earbuds will not connect or reconnect

Two-pair kit: restore listener 1 with the first NB16-Q using the steps below. Then connect the second NB16-Q to listener 2. Restore both connections before locking with buttons 1 + 2; check TV sound through both pairs afterward.

Possible cause: the NB16-Q earbuds have connected to another device, or pairing / locking needs to be restored.

For this recovery, keep the transmitter powered while the TV is OFF.
If it uses TV USB, move it to a USB wall adapter first.
Then turn the TV OFF and nearby phone Bluetooth off.

  1. Turn transmitter ON.
    Hold its listener 1 button for about 5 seconds until the nearby indicator alternates red and blue.
  2. Turn NB16-Q OFF.
    Hold its MFB for about 5 seconds, continuing past power-on until red / blue alternate and you hear “Pairing.”
  3. Keep the earbuds close to transmitter and wait for solid blue on both devices.
  4. For this dual kit, first connect the second NB16-Q to listener 2. With both pairs connected, hold transmitter 1 and 2 together for about 10 seconds until the indicator turns pink for a few seconds. Release to lock the connections.
  5. Turn both devices OFF, wait about 5 seconds, then turn the transmitter and earbuds ON.
    Wait 5–10 seconds.

Expected: both devices reconnect with solid blue lights.
Turn the TV back ON, restore normal transmitter power and confirm TV sound.

If not: reset both devices, then repeat pairing and locking.
NB16-Q / transmitter re-pair and lock reference.

Using soundbar together? More quick fixes
Second pair will not connect

Possible cause: the second NB16-Q has connected to another device, or its pairing with transmitter listener 2 needs to be restored. Use these steps only when the second pair does not reconnect after the main setup.

Before you start: turn the TV and nearby phone Bluetooth OFF.
Keep the transmitter powered by USB; use a wall adapter if TV USB turns off.

  1. Connect the original NB16-Q first

    Turn on the transmitter and NB16-Q.
    Wait for Listener 1: solid blue.
    Keep the original earbuds ON and connected.

  2. Put the second headphones in pairing mode

    Start with the second NB16-Q OFF. Hold its MFB for about 5 seconds, past power-on, until its LED alternates red / blue and you hear “Pairing.”

  3. Hold transmitter listener 2 · 5 seconds

    Wait for Red / blue alternating.
    Keep the second headphones close.

  4. Wait for both connection lights

    1 + 2: solid blue means both pairs are connected.

  5. Turn the TV on and test both pairs

    Play TV audio.
    Each listener adjusts volume on their own headphones.

Expected: transmitter listener indicators 1 + 2 and both NB16-Q LEDs are solid blue, and both pairs play TV sound. Each listener adjusts volume on their own earbuds.

Still not connected? Check the second NB16-Q is alternating red / blue and try pairing again while the first pair stays connected. Full second-listener recovery guide → or Contact Support.

Next time / use only the second pair

Next time: connect the original NB16-Q first.
Turn on the second headphones and wait 5–10 seconds.
If they do not reconnect, press transmitter 2 once.

Second pair only: connect the original pair, connect the second, then turn the original pair OFF.

HT41866-Q supports up to two Bluetooth listening devices.
Two NB16-Q pairs are included. The transmitter supports at most two listening devices; a third pair cannot be added.

Only one pair plays TV sound

Possible cause: the second NB16-Q is off, has a low battery, is connected to a phone, or has not connected to listener 2.

  1. Keep the working pair ON and connected. Check the silent pair is charged and unplug its charging cable.
  2. If the silent pair is OFF, hold its MFB for 3 seconds. Turn off Bluetooth on nearby phones previously paired with it.
  3. Keep it close to the transmitter and wait 5–10 seconds. Check listener indicators 1 + 2 and both NB16-Q LEDs are solid blue.
  4. If one indicator is not solid blue, pair the missing NB16-Q. If connected but silent, raise + on that pair and replay TV speech.

Expected: both pairs play the same TV audio; each listener controls their own earbud volume. Still silent? Contact Support with the silent pair and listener LED states.

Charge the NB16-Q earbuds

Charge each NB16-Q pair separately with its supplied USB-C charging cable. Check the charging LED on each pair.

5 V USB chargerUSB-CNB16-Q
  1. Plug in the earbuds

    Connect the supplied USB-C cable to NB16-Q and a 5 V / 1 A or 2 A USB charger.

  2. Check the charging light

    Solid red means charging.
    Allow about 2–2.5 hours.

  3. Unplug when the light goes off

    LED off means fully charged.
    Unplug the charging cable before listening.

Ready whenThe charging light is off.
Up to 20 hours of use; actual time varies with volume and use.

No charging light?

Reconnect the cable.
Try another 5 V USB source and USB-C cable.

Expected: solid red appears.
Still no light? Contact Support.

Charging tips & power FAQ

Only the NB16-Q earbuds have a rechargeable battery.
The transmitter needs continuous USB power.

Power and charging FAQ →

Use with a phone or computer

Phone / computerBluetoothNB16-Q
  1. Start with both devices off

    Turn the transmitter OFF and NB16-Q OFF.

  2. Hold the multi-function button

    On NB16-Q, hold the MFB for about 5 seconds.
    Wait for Red / blue alternating and the “Pairing” prompt.

  3. Select the earbuds in Bluetooth settings

    On your phone or computer, choose Avantree NB16T-Q or NB16T, as displayed.

  4. Play audio

    Adjust the volume on the earbuds.

Ready whenSolid blue and audio plays through NB16-Q.

Cannot connect?

Disconnect other paired devices, then repeat the steps above with your Bluetooth audio phone or computer.

Return to TV listening
  1. Turn phone Bluetooth off.
  2. Turn the transmitter ON. If NB16-Q is OFF, hold its MFB for 3 seconds.
    If already ON, leave it on.

Connected: both connection LEDs are solid blue.
Play TV audio and adjust volume in Step 4 →
Not connected? Re-pair the kit →