If you have not tried it, look here ie Jeanneau Owners Network Forum - Home
I seem to recall a few folks with issues as you mention and some threads on that forum. As I doubt you will find someone with a Sun 2000 here.
If you go to http://jeanneau.tripod.com/index.htm
you will find a list o owners that have registered their Jeanneau's, you might try emailing some of the ones listed in the sun 2000 area.