City, back to one of your original questions, no you can not fix bad sectors. Bad sectors are not uncommon and part of the fromating process is to identify bad sectors as unusable and make sure data is not written to them.
Make sure you have everything important backed up. If you are getting that message now it could mean the drive is getting worse.
On an 80 conductor cable every other wire is grounded to prevent cross talk. Maybe there is a problem with the ground connection. Try reseating each end of the cable and see if that does anything.