Unable to charge the battery.

  • Turn off the headphone amplifier and charge the battery again.
  • Check that the DC IN 5V / CHARGE port of the headphone amplifier and your computer are firmly connected using the micro-USB cable (supplied).
  • Check that the computer is turned on and not in standby, sleep or hibernation mode.
  • Check that the headphone amplifier and the computer are directly connected, and not via a USB hub.
  • Try the USB connection procedure again in cases other than those stated above.
  • The USB port of the connected computer may have a problem. Connect the headphone amplifier to another USB port of the computer if available.
  • A USB AC adaptor that is not recommended is being used.
  • Connect your computer or a USB AC adaptor to the DC IN 5V / CHARGE port of the headphone amplifier.
  • The battery is fully charged.
    If the battery is fully charged, the CHG POWER indicator may blink in red and go off, and charging may not start. This is not a malfunction.
  • If the headphone amplifier has not been used for a long time, it may take a while for the CHG POWER indicator to light up in red when the headphone amplifier is connected to your computer or an AC outlet to charge the battery. In this case, do not disconnect the micro-USB cable from the headphone amplifier, and wait until the CHG POWER indicator lights up in red.
  • When Windows 8.1 is used for your computer, update your system to the latest version using Windows update.