How-to

Android / iOS devices:
Short-press the Button to activate the Voice Assistant.

Nothing Phone:
The "Button" doesn't activate the Voice Assistant by default. To enable it, open the Nothing X app, go to Controls > Button, and assign either the single press or Press & hold gesture to the Voice Assistant. Once configured, the assigned gesture will activate your Voice Assistant.

For more functions, please download the Nothing X app, available for download on Google Play and iOS App Store.

1. If the headphones have established connections with two phones, and neither phone is in a call / voice conference, the headphones will output the sound of the phone with the incoming call.

2. If the headphones have established connections with two phones, and one of the phones is already in a call:
When the initially inactive phone receives an incoming call, you'll hear the incoming call ringtone on the headphones, and the headphone will prioritise controlling the phone with the incoming call. When you end the current call, the headphones will switch the audio channel to the phone with the incoming call.

Note: Please visit the official Nothing website to learn more about Dual Connection and view the product instructions. Alternatively, contact our Customer Service for assistance.

1. If the headphones establish connections with two devices, and both phones are in an idle state:
a) The headphones will output the sound from the phone that's receiving an incoming call or making an outgoing call.
b) The headphones will output the sound from the phone that starts playing music first.

2. If the headphones establish connections with two devices, and one of the phones is playing back music:
a) The headphones will mute the currently playing music (without pausing it) and then switch to outputting the sound from the device with the incoming or outgoing call. After the call ends, the headphones will switch back to the music-playing connection to resume music playback.
b) No sound channel switching will occur when the device that started playing music later will start music playback.

The gesture controls will affect the device currently outputting audio through the headphones. If there is no audio playing, the controls will operate the last connected device or the device that most recently played audio through the headphones.

1. Auto-reconnection on Power-on / Auto-reconnection on Exiting Sleep Mode

With Dual Connection enabled:
a) When the headphones are powered on and no 3.5mm aux-in cable is inserted, headphones will attempt to reconnect if the number of connected devices is less than two. The reconnection targets the last two devices the headphones were connected to. If the headphones are enabling Dual Connection for the first time and have no prior reconnection records, they will maintain a single-device connection. (In single-connection mode, the headphones will not enter pairing mode automatically; pairing with a new device requires the user to manually press and hold the Bluetooth pairing button.) If the headphones fail to reconnect to other devices, they will remain in single-device connection mode and will not enter pairing mode.
2) After the headphones and your device are disconnected due to exceeding the connection range, the headphones will only reconnect to the phone that was disconnected due to the out-of-range issue if it comes back within the connection range again.
3) The headphones won't trigger reconnection when they are in a call or playing music.
4) If the headphones are in the reconnection state and simultaneously in a call or music playback, they will pause the reconnection within 5 seconds. If the call or music playback ends within the reconnection timeout period, the headphones will resume the paused reconnection until the reconnection times out. After the reconnection times out, the connection to the headphones can only be initiated from the device side.

2. Connection Preemption
When the headphones are in Dual Connection mode, they support connection preemption. The following rules apply when connection preemption occurs:
a) If neither of the two connected phones is in music playback state, the headphones will disconnect from the first-connected phone and connect to the device initiating the preemption.
b) When the headphones enter pairing mode with a new device:
If two devices are already connected, the headphones will disconnect from one of the devices upon entering pairing mode. After disconnecting from one device, the headphones can be detected and connected by the new device.
c) If the headphones are already connected to two devices, and a third device (with a previous connection record) initiates a preemption request, the headphones will disconnect from one of the two currently connected devices. After the disconnection, the third device can preempt and connect to the headphones.

Tips:
Music playback:
1) If one of the two connected phones is in music playback, the headphones will disconnect from the phone that's not in music playback state and connect to the device initiating the preemption.
2) If both phones are in music playback state, the headphones will disconnect from the phone whose music is not outputting through the headphones (i.e., disconnect from the device where music playback is muted) and connect to the device initiating the preemption.

Call state:
If either of the two connected phones is in a call, connection preemption is not allowed.

Press and hold the pairing button on CMF Headphone Pro for 10 seconds. The reset is complete when the red light flashes three times, followed by a flashing white light.

Once the headphones are connected to your phone, you can adjust the volume directly on your device, or roll the knob up / down on the headphones.

For more functions, please download the Nothing X app, available for download on Google Play and iOS App Store.

The Slider button on the left side of the headphones allow you to instantly adjust the intensity of bass enhancement without you having to take out your phone. This helps match the bass requirements of different music content.

Slide up to increase high / bass gain.
Slide down to decrease high / bass gain.

For more functions, please download the Nothing X app, available for download on Google Play and iOS App Store.

The Slider button is set to Bass Boost mode by default. You can switch the mode by going to the Nothing X app homepage > Controls > Slider and clicking on the settings card. The boost intensity can only be adjusted using the Slider button on the headphone.

For more functions, please download the Nothing X app, available for download on Google Play and iOS App Store.

Press and hold the Roller to switch between Active Noise Cancellation and Transparency Mode.

For more functions, please download the Nothing X app, available for download on Google Play and iOS App Store.

LDAC high-definition audio can be understood as a highway between your phone and earbuds, supporting 24-bit depth, 96 kHz sampling rate and a 990 kbps streaming rate. The high transmission bitrate ensures that high-resolution audio files are not excessively compressed, retaining more audio details and significantly enhancing sound quality.

Note: this high-definition audio requires a phone, with selected codec enabled.

For Android phones:
1. Ensure your phone supports LDAC by checking if it is enabled by default. If not, go to Settings > Developer options to check for LDAC support.
2. If your phone supports LDAC, enable it in the settings.
3. Connect the earbuds to the Nothing X app. In the app, go to Device settings. Enable high-quality audio to activate LDAC high-definition audio encoding.

Tips for optimal LDAC performance:
1. To ensure smooth playback, set LDAC playback quality to default in the phone's developer options.
2. If opting for higher-quality audio bitrate, we recommend disabling the Dual Connection feature to ensure sufficient bandwidth for LDAC high-quality streaming.

*Note: iOS devices only support the AAC high-quality audio codec over Bluetooth; other high-quality audio codecs like LDAC are unsupported.

To enhance your user experience, the Button function of CMF Headphone Pro will add a new AI Button feature when the CMF Headphone Pro is paired with a Nothing phone. This way, it’s easier for you to quickly switch and play your favourite audio content. Set as detailed below:

On Nothing OS devices:
Short-press: Activate Smart Assistant
Long-press: Activate Smart Assistant

On other Android/iOS devices:
Short-press: No function (audio source switching is not supported on third-party devices)
Long-press: Activate Smart Assistant

Note: The audio source switching function is only available when paired with a device running Nothing OS.

Power / BT Button
Power on: hold for 1 second
Power off: hold for 1 second

Pairing
Power off: hold for 3 seconds
Power on: hold for 3 seconds

Roller
Single-press: Music play / pause, answer or hang up calls
Press & hold: ANC / Transparency Mode
Double-press: Music skip forward, hang up calls or decline incoming calls
Triple-press: Music skip backward
Roll up / down: Volume up / down

Slider
Slide up / down for enhancement (0-100%)
Default bass tuning mode*

*Supports bass / treble tuning, with 2 modes available through the Nothing X app

Button
Nothing OS
Press & hold: Voice Assistant

Android/iOS
Press: Smart Assistant

More options are available in the Nothing X app.

Optional functions:

1. Spatial Audio Mode Cycle (Off - Concert mode - Cinema mode) (all platforms, with switch prompt tone)
2. Noise Control (ANC On - Transparency - ANC Off) (all platforms)
3. Mic on / off (all platforms)
4. Essential Space (Nothing OS only）