I know I had a leak. Was backing with the steering turned and suddenly, white smoke poured out from under the hood. From that moment on I had a leak. When I'd hear the whine/hum/buzz start I'd add fluid and it would go away. I changed the pressure hose and bled the system like the book told me to and haven't noticed a leak but yesterday, I was backing into a driveway with the wheel only slightly turned. I heard the whine/buzz/hum. Not nearly as loudly as before though. It went away when I was going forward.
Could there now be a problem with my pump?