My 2007 A4 radio backlight stays on. When I got the vehicle it was dead, dead, dead! Charged battery up and got engine prepped to tun on and it did. Radio needed a code and I had it and input the code and radio works. Now I see that the backlight does not turn off even when engine is off, car is locked and key is not in ignition. I saw a post here that said remove fuse then replace and radio is reset. This did nothing and the radio did not need resetting. I am thinking that a reset is a must but is their another way to reset the radio or can anyone advise how to fix the situation?