text: Three of the four units purchased, two from this seller and two from another seller on Amazon, would power up but then be totally unresponsive to either button. Had to remove the battery to shut them down. The ONE of the FOUR that works is great; the software is well designed and has all of the features that I wanted. But the manufacturer clearly has a manufacturing or circuitry design problem. Even the one that works behaves inconsistently. On powerup, sometimes it will begin automatically to record video and sometimes I have to press a button to tell it to begin recording. I would like a setting that would allow me to select that behavior, with the camera obeying the setting reliably, of course. Overall, this product is garbage due to the 75% DOA quality, notwithstanding the good software design (well designed menus).