Audio-Technica ATH-CKS50TW Noise-Canceling True Wireless In-Ear Headphones (Black) - Manual (Page 36)

Troubleshooting
35
Sound is distorted / Noise is heard / Sound cuts out
Turn down the volume on the product and the Bluetooth device.
Keep the product away from devices that emit radio waves such as microwaves and wireless routers.
Keep the product away from TVs, radios, and devices with built-in tuners. These devices can also be affected
by the product.
Turn off the equalizer settings of the Bluetooth device.
Remove obstacles between the product and the Bluetooth device and place them closer together. For
details, refer to "For a more comfortable Bluetooth communication experience" (p. 8).
The noise-cancelling effect may vary or a bleep (howling) may occur depending on how you wear the
product. In these cases, take off the product and put the product in your ears again correctly.
Cannot hear the voice of the caller / Voice of the caller is too quiet
Turn on the power of the product and the Bluetooth device.
Turn up the volume on the product and the Bluetooth device.
Confirm that the product and Bluetooth device are connected via HFP (or phone connection).
Disable pairing for the product and the Bluetooth device, then pair the product with this device again.
Switch the sound output of the Bluetooth device to the product.
Charging case cannot be charged
Securely connect the included USB charging cable and charge the product.
The charging case or headphones may be hot. Allow the temperature of the product to cool sufficiently
before charging in a well-ventilated place (10 to 35°C (50 to 95°F)) away from direct sunlight.
Headphones cannot be charged
Make sure that the product is placed in the charging case correctly.
Make sure to close the charging case cover when charging.
Charge the charging case.
Wipe dirt off the charging terminal with a dry cloth.
The charging case or headphones may be hot. Allow the temperature of the product to cool sufficiently
before charging in a well-ventilated place (10 to 35°C (50 to 95°F)) away from direct sunlight.
For details about how to operate your Bluetooth device, refer to the device’s user manual.