For my previous headunit I made a small electronic box that would control the accessory power input. It triggers by unlocking the doors, so while I was walking toward the car the headunit is already booting. This was helpful because the unit literally took over a minute before it was ready. Then I noticed on my father's car that when removing the ignition key, the radio on his bmw remains on and only when he locks the car, the volume would fade to zero. Pretty cool, I thought, so I bought the remote control for the clarion and sampled the IR commands for volume up/volume down. Then I installed