Hi, today I used the FP2 in my car. The phone was connected to my car radio’s USB port and appeared to be charging (battery flash icon visible), but in fact the battery was losing power. At 15% a warning notice appeared. Admittedly, I was using a GPS (google maps) and bluetooth to stream music and know this takes a lot of energy. But why would the smartphone’s battery need to be drained if it’s connected to USB? Is there a way to prevent this from happening? I used a charging USB cable from Google, they usually appears to be working well. Thanks.