Shrill whistling type of noise-anybody have any idea what it could be? on 1998 Mercedes-Benz SLK230

This shrill noise is intermitent and seems to stop when I speed up, yet it gets louder as I slow down and stops when the car stops. I don't think it's the AC since I turned off the AC and the noise didn't stop.
If anyone else has experienced this any information that could be passed on to me would be greatly appreciated.
Thanks, CR

Asked by for the 1998 Mercedes-Benz SLK230
I would start by checking the the condition and tension of your belts. Also look for any coolant that may be leaking on to the belts. Then I would check all the pulleys that the belts turn, there may be a bearing that is wearing out. It does not sounds like a wheel/axle type noise because that would generally intensify with speed.
I had to bring my car to the shop this morning, it was really making a strange noise. I saw one of the belts wasn't in the correctly positioned. You are right on with your answer...need a new water pump and belts. Thanks and have a great day.
1 more answer , 1 more comment
Unfortunately noises are a very subjective condition that would require us to hear to be able to determine the source. Please feel free to call us at 954-713-1000 and schedule an appointment. We could go for a test drive with you to hear the noise. Thank You
Thank you for your reply. Problem has been identified and solved.