JBL Synchros S300 On-Ear Stereo Headphones User Manual

Introduction

The JBL Synchros S300 are on-ear stereo headphones designed for audio playback. They feature a durable construction, comfortable ear cushions, and a detachable cable with an in-line universal remote for convenient control of music and calls. This manual provides instructions for setting up, operating, and maintaining your Synchros S300 headphones.

JBL Synchros S300 On-Ear Stereo Headphones, Black/Blue

Image: JBL Synchros S300 On-Ear Stereo Headphones in black and blue, showing the left earcup with JBL logo, adjustable headband, and the blue detachable cable.

Package Contents

Please verify that all items listed below are included in your package:

JBL Synchros S300 On-Ear Stereo Headphones
Detachable Audio Cable with Universal 3-Button Remote
Protective Carrying Case

Setup

Connect the Audio Cable: Locate the audio input jack on the left earcup of the headphones. Insert the smaller end of the detachable audio cable firmly into this jack. Connect the 3.5mm plug of the cable into the audio output of your device (e.g., smartphone, tablet, computer).
Adjust the Fit: Gently extend or retract the headband slides to adjust the headphones for a comfortable and secure fit over your ears. The earcups should rest comfortably on your ears without excessive pressure.

Operating Instructions

Audio Playback

Ensure the headphones are properly connected to your audio source.
Start audio playback on your connected device.
Adjust the volume using the in-line remote control or your device's volume controls.

Using the Universal 3-Button Remote

The in-line remote provides convenient control for music and phone calls. Functionality may vary slightly depending on your connected device (iOS or Android).

Center Button:
- Press once to Play/Pause music.
- Press once to Answer/End a call.
- Press twice to Skip to the next track.
- Press three times to Go to the previous track.
Volume Up (+) Button: Press to increase audio volume.
Volume Down (-) Button: Press to decrease audio volume.

Close-up of JBL Synchros S300 in-line remote on blue cable

Image: A close-up view of the blue detachable cable, highlighting the black in-line remote with three distinct buttons for control.

Folding for Storage

The Synchros S300 headphones feature a fold-flat design for easy portability and storage. Gently swivel the earcups inward until they lie flat against the headband. Place the folded headphones into the provided protective carrying case to prevent damage.

Maintenance

Cleaning Ear Cushions: Wipe the soft leather ear cushions with a dry, soft cloth. For stubborn dirt, a slightly damp cloth can be used, but ensure the cushions are completely dry before use. Avoid harsh chemicals or abrasive cleaners.
Cleaning Headband and Frame: Use a dry, soft cloth to clean the headband and frame.
Storage: When not in use, store the headphones in their protective carrying case to shield them from dust, scratches, and impacts. Avoid storing in extreme temperatures or high humidity.
Cable Care: Handle the detachable cable gently. Avoid sharp bends or excessive pulling.

Troubleshooting

Problem	Possible Cause	Solution
No sound from headphones.	Cable not fully connected. Device volume too low or muted. Incorrect audio output selected on device. Damaged cable.	Ensure both ends of the audio cable are securely plugged in. Increase volume on both the headphones' in-line remote and the connected device. Check for mute settings. Verify the correct audio output is selected in your device's settings. Try a different audio cable if available.
In-line remote not responding.	Cable not fully connected. Device compatibility issue.	Ensure the audio cable is securely connected. While the remote is universal, some functions may have limited compatibility with certain non-standard devices.
Audio quality is poor or distorted.	Loose cable connection. Source audio quality is low. Damaged cable or headphones.	Check and re-secure cable connections. Test with a different audio source or higher quality audio files. If issues persist, the cable or headphones may be damaged.

Specifications

Model Name: Synchros S300
Connectivity Technology: Wired
Included Components: Cable, Protective Case
Material: Leather (ear cushions)
Compatible Devices: Universal
Cable Feature: Detachable
Control Method: Remote (3-button universal)
Audio Driver Type: Dynamic Driver (40mm)
Ear Placement: On Ear
Form Factor: On Ear
Headphones Jack: 3.5 mm Jack
Item Weight: 11.2 ounces
Product Dimensions: 6.77 x 3.54 x 8.5 inches
Color: Black/Blue
UPC: 050036320252

Warranty and Support

JBL products are designed for reliability and performance. For detailed warranty information, please refer to the warranty card included with your purchase or visit the official JBL website. For technical support, product registration, or service inquiries, please contact JBL customer support directly through their official channels.

Official JBL Website: www.jbl.com

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