I have a mac cube that ran fine for about a year and the hd failed so I put a drive I pulled. this drive worked for a couple of months and it started having problems it would spool up the wind down to a stop, start stop over and over it was about 2 sec up and 2 sec down. so i ordered a new drive from owc and put it in worked ok for about a week and the same thing started spool up and down. What could be the issue power supply?