It's tough to know the level li-ion batteries so the meter is an estimate based on how the battery behaved in the past. It's calibration can get messed up causing it to read incorrectly. One thing to try is leave it on until the unit shuts off by its self and then fully charge it. This can reset the meter calibration. If the meter is showing low prematurely, you try the same thing. This will sometimes reset the meter calibration. The unit will shut off before draining the battery low enough to damage it. In general, of course, it's best not to routinely let the battery get that low. You'll get the most use out of Li-ion batteries by keeping them cycled between ~95% and ~50%.