I recently bought a 2010 Dodge Challenger with a Pioneer avic x930bt already installed in it. Everything was fine for the first few weeks, but last week I went to start the car only to find the battery dead. [This is not my daily driver, it had sat for about 2 weeks.] I didn't think much of it as it had an older battery and hadn't been run.
I jumped the car and everything seemed to be fine. It didn't register until later that the radio had come on when the cables were connected without the key on. When I went to shut the car off, same thing, the radio stayed on after the key was removed