i've got a '02 a4 1.8t and my radio crapped out today. hoping someone could help me out.

i turned on the car and my radio just didn't work. it is on, but the display is orange with no lettering. i can tell it's on as the lights on the radio are all on and the display, though not displaying any numbers or letters, is orange. it doesn't respond to any of the buttons.

to make matters worse, when i turn the car off, the radio doesn't go off. meaning that my battery is slowly being drained. i can't turn the radio off.

any suggestions?