Yes the app sucks. Yes the stereo isn't super-loud if the input source is weak, but...
I've only had mine a little over 1/3 of a year, but since I charge slow, I charge often, yet it has never once failed to charge, or stopped charging, so...
I wonder if they accidentally had the car's charge-preventing timer activated. I know that sounds obvious, but so is starting the car, & they didn't figure that out in 2 years (between the two of them).