Hi Rolf,
I'm sorry you are having problems with your drive. From the description of your problem, it sounds like you have a controller card issue, and you will need to send it in for repair. Go to our website and fill out the RMA request form here:
http://www.g-technology.com/Support/Support.cfm?Loc=Contact. Check the save data option and we will do what we can to recover your data. Please let me know if you have any questions.
Regards,
Gene Gilbert
g-technology.com