There's news lately that charging the battery while the unit is on may actually damage the radio/transmitter. It's an ongoing development. I have 4 TID H3s and one went bad. I have started charging the batteries while the units are off, and also I suggest NOT using the dock. The battery rarely seats well in the dock and I feel like it overcharges the battery.
On a positive note, TID replaced my H3 free of charge after I sent them a video. Even though the bad radio can no longer TX, it can RX pretty well, so I turn it on when I want to monitor more channels.
See video below: