Hi @Lcolville77 -
The issue is definitely related to QGround Control! You need to properly set your battery capacity within the program. To do so, go to Vehicle Setup by clicking the purple Q in the upper left, and select Power on the left. Set the capacity to the correct number of mAh (15600 or 18000, depending on your battery)
Note - the vehicle assumes the battery is fully charged when powered on, so if you use half the battery and then restart the autopilot, the capacity readout will be ~50% inaccurate!
I typically prefer to set the capacity to -1, so I can monitor battery voltage directly, as mentioned here.