Monster Open Ear AC328 Bluetooth Headphones

Quick Start Guide

Product Overview

Open earphones x2 (Left & Right)
Charging case x1
USB-C cable x1
Quick start guide and warranty card

Charging

Before using the "Monster Open Ear AC328", connect the USB-C cable to a power adapter to begin charging. Fully charge the earphones and the charging case before the first use.

Features a USB-C Port for charging.

Power On/Off

Earphones automatically turn on when the charging case lid is opened. To turn off the earphones, place them in the charging case; they will charge and turn off simultaneously.

Pairing

The earphones will turn on automatically when taken out of the charging case.

For new device connection: Turn on Bluetooth on your device and select "Monster Open Ear AC328" from the list. You will hear system prompts upon successful connection. If previously connected, earphones will automatically connect to the last paired device upon powering on.

Wearing

Place the "Monster Open Ear AC328" earphones into your ears and gently rotate them to achieve a comfortable fit for optimal wearing and sound quality experience.

MFB Operation

MFB (Multi-Function Button) controls:

Answer/End Call: Double-tap the MFB on either the left (L) or right (R) earphone.
Reject Call / Activate Voice Assistant: Press and hold the MFB on either earphone for 2 seconds.

LED Indicator (Earphone)

Status	Indicator
Power On	White flashes
Power Off	Red light on for 2 seconds, then turns off
Pairing Successful	White light on for 1 second, then turns off
Pairing Timed Out	Red light on for 2 seconds, then turns off
Connection Lost (Over Distance)	White flashes
Disconnect Phone	White flashes
Low Battery	Red light flashes slowly
Low Power Off	Red light on for 2 seconds, then turns off

LED Indicator (Charging Case)

Status	Indicator
Charging	Red light continuously flashes slowly; turns solid red when fully charged.
Discharging (Case charging earphones)	White light stays on while charging earphones; turns off when earphones are fully charged.
Low Battery	White flashes

Reset

To reset the earphones to factory settings: While the earphones are powered on, touch the MFB on both earphones simultaneously 5 times. The earphones will automatically shut down. Place them back into the charging case and then remove them; they will power on automatically and enter pairing mode.

Attention

Private replacement of batteries without permission is not recommended.
Batteries [battery packs or battery combinations] should not be exposed to lighting, baking, or similar overheating environments.
The input voltage and current standard for charging the headset charging compartment from an external power source should be ≤ 5V/1A.

FCC Caution

This device complies with Part 15 of the FCC Rules. Operation is subject to the following two conditions: (1) This device may not cause harmful interference, and (2) this device must accept any interference received, including interference that may cause undesired operation.

Any changes or modifications not expressly approved by the party responsible for compliance could void the user's authority to operate the equipment.

Note: This equipment has been tested and found to comply with the limits for a Class B digital device, pursuant to Part 15 of the FCC Rules. These limits are designed to provide reasonable protection against harmful interference in a residential installation. This equipment generates uses and can radiate radio frequency energy and, if not installed and used in accordance with the instructions, may cause harmful interference to radio communications. However, there is no guarantee that interference will not occur in a particular installation. If this equipment does cause harmful interference to radio or television reception, which can be determined by turning the equipment off and on, the user is encouraged to try to correct the interference by one or more of the following measures:

Reorient or relocate the receiving antenna.
Increase the separation between the equipment and receiver.
Connect the equipment into an outlet on a circuit different from that to which the receiver is connected.
Consult the dealer or an experienced radio/TV technician for help.

The device has been evaluated to meet general RF exposure requirement. The device can be used in portable exposure condition without restriction.

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