FODSPORTS FX8 Air Manual página 10

Battery detection & low battery automatic reminder function
FX8 AIR has the power detection function. When the device is turned on, short press the
"Previous" button and the "Next" button at the same time.
Power over 90%, the voice will prompt: "beep...beep...beep".
Power over 50%, the voice will prompt: "beep...beep ".
Power lower than 50%, the voice will prompt:"beep...".