Mercedes 2006 c350 Radio on no key Fan full blast no key Sent ecu out no issuesfound

Hello, any guess on why the radio would randomly blow a fuse? Has there been any work done in this area? Any modifications? My guess is that there is some kind of wiring concern that is causing the full power to the fan. I don't think it's a random happening; I suspect there is more to the story here. Any more info?