Top-10 Headphone Defects Every Buyer Should Know

Quality earphones keep your ears safe and music loud. To guarantee the quality to your customers, it is important to set a level of expectations for your supplier and define acceptable and unacceptable headphone quality in your order.

To help you with that, V-Trust Team has prepared a list of Top-10 common defects of earphones that every buyer should know. Read about their main causes and recourses, and remember to include them in your checklists for upcoming inspections!

1. No sound

As an earphone product developer, you want your goods to function flawlessly. A defect of no sound, that indicates malfunction of your products, will really detract from your quality level, thus you need to pay additional attention to check it thoroughly while goods are still at the factory.

V-Trust inspectors, during earphone inspections, check full sample size for function defects.

Causes:

1. If earphones have no sound, best to ask factory workers to look into its components. Speaker driver or speaker components might be broken or disconnected. To solve the problem, ask the factory to replace speaker components.
2. Check the welding of wires, and ask to replace the connecting wires if needed

 2. Inconsistent sound between the left and right channels

In inspection of earphones, while checking function of full sample size, V-Trust inspectors will compare the sound quality of both earphones. If any inconsistencies are found, we will make remarks about them in the report.

Cause:

1. The speaker components in left and right earphone have different specifications or are defective. To solve this problem, ask factory to change the speaker components

3. Static or hissing sound

Static sounds are very common defects in earphone and headphone inspections. You can prevent it early before goods leave the factory, by asking inspector to conduct the function check on earphones sound quality and spot hissing noise.

Cause:

1. Defective speaker diaphragm, or wrong assembly of a diaphragm

4. Frequency response check failed

During the inspection, we check the frequency response of earphones as well for both left and right channels to make sure that they are within the frequency range and sound is not distorted.

Cause:

1. The quality of speaker and driver units are not conforming to the specifications 

5. Loose wires

Any loose wires pose safety risks for the user. That is why during the inspection we will conduct pull test on the wires and cables to check the quality of welding and assembly.

Cause:

1. Poor welding and attachment of wires, problem treatment: re-reinforcement welding

6. Absence of left or right channels

In some cases, while checking the function of earphones, you might find that there is no division of left and right channels in the actual product, even though it is stated on the manual. You can check the circuit to find the cause of this problem.

Cause:

1. The earphone’s circuit is designed for the mono channel. To solve the problem, ask the factory to change the circuit design

7. Impedance of earphone is different than spec

Incorrect impedance influences the sound quality of earphones, that’s why this important test is included in our checklist for headphones inspections.

Cause:

1. Incorrect components, or wrong specifications

8. Buzzing sound

If inspector finds your earphones buzzing when functioning, the speaker components might be assembled wrong during production.

Cause:

1. Loose speaker components, that need to be tightened and re-assembled

9. Unable to pair by Bluetooth

Bluetooth pairing is one of the mandatory tests in our earphone inspections, which is conducted on full sample size of checked products. If your earphones / headphones are unable to pair, ask factory to recheck the Bluetooth module.

Cause:

1. Damaged Bluetooth module, which needs to be replaced

 10. Bluetooth headset is unable to charge

If during charging and discharging check, inspector found that earphones are unable to charge, the problem should be searched for in the charging circuit; it might be broken or disconnected.

Cause:

1. Charging circuit is broken or disconnected

As you can see, the main causes of headphones / earphones defects are due to wrong or defective components, or the quality of assembly. You can prevent these defects by conducting a Pre-Production Inspection on the quality of components, or During Production Inspection to check the quality of assembly at the production line.

Keep in mind that for electronic and electric products it is important to conduct internal checks during the inspection to check the quality of components against the confirmed CDF (Component Data Form), and quality of welding.

V-Trust can help you with Product Inspections and Factory Audits for your headphones / earphones supplier in in China, India, Vietnam, Bangladesh and Malaysia. Our full-time inspectors and auditors will help to spot the non-conformities of your earphones to ensure the quality of your goods and ultimately your reputation.