Guess this Rattle/Whining Noise From Engine
 

I have a 2006 BMW 530i w/ 125,000 miles The rattle/whining noise starting about 6 months ago and has not gotten any worse. It appears to be coming from the alternator area. I am not sure if it's the alternator, belt tensioner, pulley, vacuum pump or something else. The ticking noise does not appear to be coming from the valves. Click on the You Tube Link to view video.

BMW 530i Ticking Noise - YouTube

You gotta do a little digging yourself as it could be a number of things. First I'd remove the belt(s), inspect it and check the tensioners. It(tensioners) could be loose or going bad. Inspect the pulleys on alt, pumps and ac compressor. Finally getting a mechanics stethescope can help and pinpoint the problem area. In my case it helped me determine that my water pump was bad. Good luck