Bmw X6 - No acoustic sound

[Sh02X6]

Hi guys, I need your help! A friends car was stolen and then recovered. The sound does not seem to work any longer, fuses have been checked also and they seem fine. There is no sound at all, no parking sensor or radio sound absolutely nothing. Also getting an sos error. I’ve followed some YouTube videos and pulled out the wires form the amplifier and there is no red light on the optical cable, also the roof lining has been messed with and not sure why the thieves would’ve messed with it? Not sure if something was stolen from it or what’s really happened.

Hope for some help, it’s a e71

Thank you