2004 330CI Radio Problem

Hey everyone I came across your forum while looking for some help with my 04 330CI cont. The navigation screen recently started scrolling while the radio was playing. Subsequently the screen went blank but I still had the radio for a couple of days and was able to switch channels and control volume with the steering wheel. Well now everything has stopped working. I've been researching and ending up buying a new MKIV DVD drive after a repair shop told me that was the issue. I plugged up the new DVD drive today and nothing happened still the same issue. I have no radio, no navigation no nothing. Any suggestions would be helpful.