For the past couple months every 15 mins or so I get a wierd noise coming from my Mac Pro. It sounds like a zoom but as if the zoom was shuting down. Sort of like a loud fan shuting down even though the fans are never loud. This seems like it started happening when I added a new 1 TB WD Black HD in my Mac pro a month after receiving it. If this is the HD do you think i have any thing to worry about as the computer runs great and there is no problems with the HD.