Whistling at idle and off throttle/ no load

I just dropped the TDI off at the stealership for whistling at idle and off throttle condition under 1700 rpm. Service tech suspected it was the turbo bypass valve. Anyone else have this experience?

Are you sure it's not just your turbo you're hearing !!! Mine starts up a few seconds after starting and definitely best described as a 'whistle' sound. It wanders up and down a bit. In fact, at idle and lower rpm's is the ONLY time I hear it. It's best observed from outside the car. While driving, even with the windows down, I never hear it working. Then again, that could be a byproduct of playing in bands for years where loud=good

No. This started on 20 July and got progressively louder until this morning. It was different from the turbo sound. This is much louder that the turbo whistle. I do hear the turbo when my windows are down. I keep them down for that fact. This noise was strange and diffent. All most like a steering pump right before it goes...but in a milder form. Still have not heard from the dealership.

I had a whistling during low speed acceleration, it turned out to be a plugged snowscreen and it was the air entering the bypass valve. I had about 38K miles on the car.