I picked up my smart today and everything is fixed.
The fault codes were all related to low voltage but the battery, charging system and alternator checked out OK. Nothing had to be replaced, just reset.
They agreed with others in this thread that the "old walkman radio" probably caused a voltage spike or some such thing.
The shift out of Park was checked but attributed to the low voltage fault.
I am now successfully using the AuxInput with my IPod lookalike.
They did the work under warranty with no charge. I am even more happy with the San Jose dealer.
The bottom line is:
don't plug really old portable devices into the AuxInput port