Bipper MOST bus fault

I had a similar issue with my Audi A6. Same symptoms: no sound, nav system dead, and a MOST bus error. The MOST bus handles data between control units via fiber optic, so a break can cause a system-wide failure. Did you check all the control units?

Thanks. When you say check the control units, what did that involve? I'm not an expert, but I did check the fuses.

The fault was in a control unit on the MOST bus. Given the symptoms and error code, a systematic diagnostic process is needed to pinpoint the faulty unit. The MOST bus is a ring, so a defective unit interrupts data flow. I'd recommend professional diagnostics to avoid more issues. That's what I did with the Audi.

Thanks, that's what I needed to hear. I took it to a workshop, and they confirmed a faulty control unit on the MOST bus after diagnostics. Repair cost is about 1000€, including the unit and labor.