If the headset detects a problem while charging due to following causes, the indicator (red) may turn off or flash although charging is not complete. In this case, charge again within the charging temperature range. If the problem persists, consult your nearest Sony dealer. A commercially available USB AC adaptor capable of supplying an output current of 0.5 A (500 mA) or more Personal computer If the headset is not used for a long time, the indicator (red) may not light up when you connect the micro- USB cable to charge the headset. Wait for a specified amount of time until the indicator (red) lights up. Time required for charging the empty battery to its full capacity. The charging time may differ depending on the conditions of use. The headset cannot be charged when the computer goes into standby (sleep) or hibernation mode. In this case, change the computer settings, and start charging the headset once again.

Sony WH-1000XM4 Wireless Noise Cancelling Headphones Sony WH-1000XM4 Wireless Noise Cancelling Headphones

The headset can be also charged by connecting the headset to a running computer using the supplied USB Type-C cable. The headset cannot be turned on, nor can the BLUETOOTH and noise canceling functions be used, during charging. You can use the headset by connecting the supplied headphone cable, even while charging the headset.If the headset detects a problem while charging due to following causes, the indicator (red) may turn off, although charging is not complete. In this case, charge again within the charging temperature range. If the problem persists, consult your nearest Sony dealer. If the headset is not used for a long time, the rechargeable battery usage hours may be reduced. However, the battery life will improve after a few recharges. If you store the headset for a long time, charge the battery to its full capacity once every 6 months to avoid over-discharge. If you store the headset for a long time, charge the battery to its full capacity once every 6 months to avoid over discharge.

WH-1000XM4 | Help Guide | Charging the headset - Sony

If you store the headset for a long time, charge the battery to its full capacity once every 6 months to avoid over-discharge. Time required for charging the empty battery to its full capacity. The time may be different depending on the conditions of use. The remaining battery charge of the headset is not displayed on the screen of an iPhone or iPod touch.If the life of the built-in rechargeable battery drops significantly, the battery should be replaced. Consult your nearest Sony dealer for replacement of the rechargeable battery. The noise canceling function cannot be used while charging or if kept connected to the computer after charging is complete. Use the supplied micro-USB cable only, and connect directly to a computer. Charging will not be completed properly by an indirect connection, such as via a USB hub. If the headset is not used for a long time, the indicator (red) may not immediately light up when charging. Please wait a moment until the indicator lights up.

WH-1000XM3 | Help Guide | Charging the headset - Sony

If the usage hours of the built-in rechargeable battery decrease significantly, the battery should be replaced. Consult your nearest Sony dealer to replace the rechargeable battery. If the headset is not used for a long time, the indicator (red) may not light up when you connect the micro-USB cable to charge the headset. In this case, do not disconnect the micro-USB cable from the headset: wait a few minutes until the indicator (red) lights up. If the rechargeable battery has not been used for a long time, its duration may shorten. However, the battery life will improve after a few recharges. If the headset detects a problem while charging due to the following causes, the indicator (red) flashes. In this case, charge once again within the charging temperature range. If the problem persists, consult your nearest Sony dealer. Connecting the headset to both a music player and a smartphone / mobile phone (multipoint connection)