You could do that, but that still didn't answer his question. I believe he wants to start up the car without having the unit go through the startup cycle again. Joker>You can only have one or the other. Either have the unit stay on forever cuz there is no way you can turn off the unit when leaving the car "IF" you connect the two wires, ACC and Power wire together to the 12+V constant wire of the car, bypassing the ACC.
The reason why there is a hicup when starting up the car is because at the back of the key switch on your steering wheel are series of connections that makes contact to series of wires. When the key turns, it will turn the switch to those wires thus making contact. In between contact, there is a delay. ACC turns on accessories and is connected to a fuse to the battery. Ignition on turns all power in the vehicles engine, fuel pump, etc. Turn one more and starts the car, which fires the alternator to send spark to the sparkplug, which basically has no power from the battery. Therefore, there are no volts going to the deck and other areas, needs 12 volts constant to the alternator to start the car, no interference.
Solution, you can connect a seperate battery with/or a capacitor and a switch to it to your deck. Using the switch to control the power going to your deck. JUST A THOUGHT.