Wireless headphones charged for four hours are not full, should consider the following points:
1. When the headset is purchased soon, the battery capacity is relatively sufficient, and the charging time will be longer.
2. The charger problem, when the charger output voltage is low, or the internal capacitor is deteriorated, the charging time will be longer, and it may also make the battery heat.
3. Battery reasons, when the battery sound leakage, performance deterioration, or battery charging monitoring circuit failure, four hours of charging or display dissatisfaction.
First of all, try to change the charger charging line, if it is still dissatisfied may be a problem with the Bluetooth headset battery, if the battery is wrong, it is recommended to replace the battery to avoid danger.