While you wait for answers, we may have found some information which could help you.
Click here for Repair Sony Stoppedsony walkman?
Read error C13 on Sony Minidisk player/recorder?
Sony JA20ES minidisc.....needing repair?
Sony personal minidisc system ZS-M7?
How can I get the AMS knob to work correctly?
Sony Walkman W380i?