Despite being fully charged, my transmitter no longer powers up. And before you ask, yes, I press and hold the power button until the LED indicates it's on. I've owned my 4K for only two short months, and have barely even flown it. I've never dropped anything, and have taken immaculate care of my bird/transmitter. * Update. I was able to turn in on. However, something is definitely a bit corky with the transmitter. Has anyone experienced this?