I drive a V70 D5 MY 2006 with full equipment: HU 850, telephone, Navi. Yesterday first time: silence in the car, only a recurring cracking in the speakers at the same time intervals. No radio sound – but all keys work, the CD changer too. After turning off and restarting – there was sound again. Yesterday again – silence. But also the cracking in the speakers. Strangely enough, even when the radio is off… help… what do?