The stock radio in my 97 740il has gone from intermittent to totally dead. CD and CD changer working perfectly. In past radio would work if I swapped from CD mode to FM mode a couple of times. Head unit displays fine, but no sound and can't find a station on seek. Could it be antenna/booster failure - where are they? Head unit includes radio, cd and computer functions - part of premium audio upgrade (Alpine?) of that era.
