If you play loud it might be the music that trigger the G-sensor in the camera to create a event file, try and disable use of G-sensor or change to lowest sensitivity setting.
IMO you should not use G sensor when driving, the camera record all the time so you will only loose stuff if you have a really small memory card or drive for really long time after a event you want to save.
I recommend to use the manual event button for the little things, and should you get in a major accident where you can not press the event button the first thing people should do coming to your aid is to turn off your car, and so nothing more will be recorded and your event are safe on the memory card.