IMO it's time to replace it. I have had my drive do the same thing, nothing worked. But when I replaced it... All was well. Have you cleaned it/checked for problems/dropped it?
Warranty was over way over by then and my father got it done not me.
He's a noob.
To tell the truth, afterwards I was all "wasn't that a little expensive? Should have just replaced it,"
But he claimed a lot of other stuff got fixed as well.
Actually I just take apart the stuff for salvagable parts like motors and teeny tiny screws. Some shops also trade them in for their precious metals. So I tend to stockpile old computer parts