I have the same problem. I have 2 48GB IBM drives. It only started happening after I went from 1.03 to 2.0BXX. I have not backreved yet as it has not happened in a few days. It is interesting that it was warm the last 7 days and it has not happened. I do not think it is a cable as I have left the unit untouched in the dash and it went from working to not working and vice versa.

Steve