While driving, the power to the unit often turns off and on repeatedly, which becomes so annoying that I just wind up unplugging it. I’m using the N4 with the Vantrue windshield GPS mount. I’ve heard this could be related to the use of a non-recommended or full memory card, but I’m using the Vantrue Cycle 256 GB microSDXC card and it’s only about 60% full. I’ve checked several times, and all electrical connections are tight. This same problem occurs while using the unit in different vehicles, and the blue light on the power cord plug always stays lit even when the unit shuts off, so it‘s an issue with the unit, not the car. Any suggestion?