A couple months ago I started my car one morning and heard what sounded like a high pitched screeching metallic noise (sorry that's not a very good description). I popped the hood and listened to where it was coming from and it seemed like it was coming from the power steering pump. I turned off the car turned it back on and there was no noise. I let the car run for a few min and the noise only briefly came back once. That was a couple months ago. Yesterday I started the car and heard the noise again. The noise stopped while I was backing out and turningout of my parking spot, but then came back whenI was turning out the driveway of my building. After I turned out the noise went away. I did about 30min of city driving that trip with multiple turns and the noise never came back. A few hours later when I left my building again the noise briefly returned when I first started the car but that was it. I know I'm not giving you guys too much to work with here but does anyone have any idea what this could be? It's a 1996 960 with a little over 92k. The steering feels fine even when I hear the noise and there is plenty of fluid. Thanks for your help

Tom