XC70 problem - sunroof, map lights, door locks

[LLee]

Since puchasing my 2004 XC70 (new), periodically, none of the following work:
sunroof, door lock button on doors, map lights, sunvisor vanity lights

The only way I can 'fix' the problem is by turning off the car, taking the key out and restarting the car.

It has been to the dealer 8 (yes, eight) times for this problem. The problem happens sporatically and is not reproducible so they are having a hard time pinpointing the root problem. They re-uploaded some software; they've replaced the Upper Electrical Module (where the map lights and sunroof button are located). None of these solved the problem. I'm extremely frustrated with Volvo.

Anyone heard of this before and/or have any suggestions or solutions?

Thanks!